Document and Entity Information [Abstract] Document and Entity Information [Abstract] Statement [Table] Statement [Line Items] Document Type Amendment Flag Document Period End Date Document Fiscal Period Focus Document Fiscal Year Focus Entity Registrant Name Trading Symbol Entity Central Index Key Current Fiscal Year End Date Entity Filer Category Entity Common Stock, Shares Outstanding Consolidated Balance Sheets [Abstract] Assets [Abstract] Assets Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Cash and cash equivalents at beginning of year Cash and cash equivalents Available-for-sale Securities, Current Marketable securities Amount of investments in level 1 mutual funds related to a non-qualified supplemental executive retirement plan and a non-qualified pharmacist deferred compensation plan for certain of its associates. SERP Investment SERP investment Accounts Receivable, Net, Current Accounts receivable, net Inventory, Net Inventories Prepaid Expense, Current Prepaid expenses and other current assets Income Taxes Receivable, Current Income taxes recoverable Assets, Current Total current assets Property, Plant and Equipment, Net Property and equipment, net Goodwill Goodwill Intangible Assets, Net (Excluding Goodwill) Intangible and other assets, net Assets Total assets Liabilities and Stockholders' Equity [Abstract] Liabilities [Abstract] Liabilities Accounts Payable, Current Accounts payable Accrued Liabilities, Current Accrued expenses Self Insurance Reserve, Current Accrued self-insurance Deferred Revenue, Current Deferred revenue, net Accrued Income Taxes, Current Income taxes payable Deferred Tax Liabilities, Current Deferred income taxes Liabilities, Current Total current liabilities Total current liabilities This represents the noncurrent liability recognized in the balance sheet that is associated with the Company's postretirement defined benefit plan, the Deferred Compensation Plan, as well as noncurrent liabilities related to the non-qualified supplemental executive retirement plan (SERP) and the non-qualified pharmacist deferred compensation plan as of the balance sheet date. Both the SERP and the pharmacist deferred compensation plan are designed to provide retirement benefits and salary deferral opportunities because of limitations imposed by the Internal Revenue Code and the Regulations implemented by the Internal Revenue Service. All three plans are unfunded and accounted for on an accrual basis. Postretirement benefit obligations Self Insurance Reserve, Noncurrent Accrued self-insurance Deferred Tax Liabilities, Noncurrent Deferred income taxes Other Liabilities, Noncurrent Other Liabilities Total liabilities Total liabilities Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Shareholders' Equity Common Stock, Value, Issued Common stock, no par value, 100,800,000 shares authorized, 33,047,807 shares issued, 26,898,443 shares outstanding Retained Earnings (Accumulated Deficit) Retained earnings Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Accumulated other comprehensive income (Net of deferred taxes of $3,121 in 2015 and $3,371 in 2014) Stockholders' Equity before Treasury Stock Shareholders' equity before treasury stock Treasury Stock, Value Treasury stock at cost, 6,149,364 shares Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total shareholders' equity Total shareholders' equity Liabilities and Stockholders' Equity Total liabilities and shareholders' equity Total liabilities and shareholders' equity Common Stock, No Par Value Common Stock, Shares Authorized Common Stock, Shares Authorized Common Stock, Shares, Issued Common Stock, Shares Issued Common Stock, Shares, Outstanding Common Stock, Shares Outstanding Deferred Tax, Other Comprehensive Income Treasury Stock, Shares Treasury Stock, Shares Consolidated Statements of Income [Abstract] Sales Revenue, Goods, Net Net sales Cost of sales consists of direct product costs (net of discounts and allowances), warehouse costs, transportation costs and manufacturing facility costs. Also included are vendor allowances recorded as credits in cost of sales. Cost of sales, including warehousing and distribution expenses Gross Profit Gross profit on sales Selling, General and Administrative Expense Operating, general and administrative expenses Operating Income (Loss) Income from operations Income from operations Investment Income, Net Investment income (loss) Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Cumulative Effects of Changes in Accounting Principles, Noncontrolling Interest Income before provision for income taxes Income before provision for income taxes Income Tax Expense (Benefit) Provision for income taxes Provision for income taxes Net Income (Loss) Attributable to Parent Net income Net income Weighted-average shares outstanding, basic and diluted Common Stock, Dividends, Per Share, Declared Cash dividends per share Earnings Per Share, Basic and Diluted Basic and diluted earnings per share Consolidated Statements of Comprehensive Income [Abstract] Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax [Abstract] Other comprehensive income (loss) by component, net of tax: Unrealized holding gains arising during period, tax Unrealized holding gains (losses) arising during period (Net of deferred taxes of $168 and $5, respectively for the 13 Weeks Ended and $243 and $824, respectively for the 39 Weeks Ended) Reclassification adjustment for gains included in net income (net of deferred taxes) Reclassification adjustment for gains included in net income (Net of deferred taxes of $7 and $21, respectively for the 39 Weeks Ended) Other Comprehensive Income (Loss), Available for Sale Securities Adjustment, Net of Tax Other comprehensive income (loss), net of tax Comprehensive Income (Loss), Net of Tax, Attributable to Parent Comprehensive income, net of tax Other Comprehensive Income (Loss), Available-for-sale Securities, Tax, Portion Attributable to Parent Unrealized holding gains (losses) arising during period, deferred taxes Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Tax Reclassification adjustment for gains included in net income, deferred taxes Consolidated Statements of Cash Flows [Abstract] Cash and Cash Equivalents, Period Increase (Decrease) [Abstract] Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Depreciation Amortization of Intangible Assets Amortization Gain (Loss) on Sale of Property Plant Equipment Gain on disposition of fixed assets Gain (Loss) on Sale of Investments Gain on sale of marketable securities Deferred Income Tax Expense (Benefit) Deferred income taxes Increase (Decrease) in Operating Capital [Abstract] Changes in operating assets and liabilities: Increase (Decrease) in Inventories Inventories The net change during the reporting period of the sum of amounts due within one year (or one business cycle) from customers for the credit sale of goods and services. Also includes the net change during the reporting period in the amount of outstanding money paid in advance for goods or services that bring economic benefits for future periods. Increase (Decrease) in Accounts Receivable and Prepaid Expenses Accounts receivable and prepaid expenses Increase (Decrease) in Income Taxes Receivable Income taxes recoverable Increase (Decrease) in Accounts Payable and Accrued Liabilities Accounts payable and other liabilities Increase (Decrease) in Accrued Income Taxes Payable Income taxes payable Increase (Decrease) in Other Operating Assets and Liabilities, Net Other Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net cash provided by operating activities Net cash provided by operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities: Payments to Acquire Property, Plant, and Equipment Purchase of property and equipment Proceeds from Sale of Property, Plant, and Equipment Proceeds from the sale of property and equipment Payments to Acquire Available-for-sale Securities Purchase of marketable securities Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Proceeds from maturities of marketable securities Proceeds from Sale of Held-to-maturity Securities Proceeds from the sale of marketable securities Payments to Acquire Businesses, Net of Cash Acquired Acquisition of business Purchase price Payments to Acquire Intangible Assets Purchase of intangible assets The net cash outflow during the period to acquire investments in level 1 mutual funds related to a non-qualified supplemental executive retirement plan and a non-qualified pharmacist deferred compensation plan for certain of its associates. Payments for SERP Investments Change in SERP investment Net Cash Provided by (Used in) Investing Activities, Continuing Operations Net cash used in investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities: Payments of Dividends, Common Stock Dividends paid Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net cash used in financing activities Cash and Cash Equivalents, Period Increase (Decrease) Net (decrease) increase in cash and cash equivalents Significant Accounting Policies [Abstract] Significant Accounting Policies [Text Block] Significant Accounting Policies Current Relevant Accounting Standards [Abstract] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Current Relevant Accounting Standards Investments [Abstract] Marketable Securities [Text Block] Investments Accumulated Other Comprehensive Income [Abstract] Stockholders' Equity Note Disclosure [Text Block] Accumulated Other Comprehensive Income Income Taxes [Abstract] Income Tax Disclosure [Text Block] Income Taxes Acquisition [Abstract] Mergers, Acquisitions and Dispositions Disclosures [Text Block] Acquisition Self-Insurance [Abstract] Accounting Changes And Error Corrections [Text Block] Self-Insurance Basis of Accounting, Policy [Policy Text Block] Basis of Presentation [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] Current Relevant Accounting Standards [Policy Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Marketable securities [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Maturities of marketable securities classified as available-for-sale [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Schedule of Error Corrections and Prior Period Adjustments [Table Text Block] Available-for-sale Securities, Amortized Cost Basis Amortized Cost Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Holding Gains Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Gross Unrealized Holding Losses Available-for-sale Securities Fair Value Available-for-sale Securities, Fair Value, Total Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Amortized Cost Basis Amortized Cost, Due within one year Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Fair Value Fair Value, Due within one year Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Basis Amortized Cost, Due after one year through five years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Fair Value Fair Value, Due after one year through five years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Amortized Cost Basis Amortized Cost, Due after five years through ten years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Fair Value Fair Value, Due after five years through ten years Available-for-sale Equity Securities, Amortized Cost Basis Amortized Cost, Equity securities Available-for-sale Securities, Equity Securities Fair Value, Equity securities Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income balance, ending balance Accumulated other comprehensive income balance, beginning balance Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Other comprehensive loss before reclassifications Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Amounts reclassified from accumulated other comprehensive income Other Comprehensive Income (Loss), Net of Tax Net current period other comprehensive loss Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Income Taxes Paid Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition Acquiree [Domain] Business Acquisition, Acquiree [Domain] C&S Wholesale Grocers [Member] C S Wholesale Grocers [Member] C&S Wholesale Grocers [Member] Business Acquisition [Line Items] Goodwill, Acquired During Period Goodwill recognized Error Corrections and Prior Period Adjustments Restatement [Line Items] Major Types of Debt and Equity Securities [Axis] Major Types Of Debt And Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Equity Securities [Member] Equity Securities [Member] Municipal Bonds [Member] Municipal Bonds [Member] Fair Value, Hierarchy [Axis] Fair Value Measurements Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value Inputs Level1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value Inputs Level2 [Member] Fair Value, Inputs, Level 2 [Member] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Accumulated Net Unrealized Investment Gain Loss [Member] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification Out Of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification Out Of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income [Member] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Domestic Country [Member] Federal [Member] Adjustments for Error Corrections [Axis] Adjustments For Error Correction [Domain] Adjustments for Error Correction [Domain] Captures the adjustments necessary for the correction of the errors related to Self-Insurance. Self Insurance Error Correction [Member] Self-Insurance Error Correction [Member] Statement, Scenario [Axis] Scenario Unspecified [Domain] Scenario, Unspecified [Domain] Scenario Previously Reported [Member] As Previously Reported [Member] Restatement Adjustment [Member] Adjustment [Member]