Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
OPERATING ACTIVITIES
Net income	$ 29,184	$ 30,015
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of operating property	8,438	7,019
Non-cash interest charges	54	55
Provisions for losses on trade and other accounts receivable	1,494	702
Gains on sales/disposals of operating property	(874)	(107)
Deferred income taxes, net	2,682	885
Stock-based compensation	1,100	1,667
Changes in operating assets and liabilities:
Decrease in trade and other accounts receivable	67,842	29,939
Decrease in other assets	9,783	11,216
Decrease in accounts payable	(51,674)	(23,862)
Increase (decrease) in other liabilities	1,724	(9,580)
Increase in insurance claims	2,285	1,321
NET CASH PROVIDED BY OPERATING ACTIVITIES	72,038	49,270
INVESTING ACTIVITIES
Sales and maturities of investments	10,636	10,651
Purchases of investments	(11,190)	(11,107)
Purchases of operating property	(828)	(2,450)
Proceeds from sales of operating property	2,273	656
NET CASH PROVIDED (USED) BY INVESTING ACTIVITIES	891	(2,250)
FINANCING ACTIVITIES
Decrease in cash overdraft	(5,536)	(6,219)
Dividends paid	(3,396)	(47,906)
Proceeds from exercises of stock options	105	429
Taxes paid in lieu of shares issued related to stock-based compensation plans	(1,527)	(2,069)
Excess tax benefits from stock-based awards	149	486
Purchases of common stock	(10,228)	(31,300)
Principal payments on capital lease obligations	(11,315)	(9,218)
NET CASH USED BY FINANCING ACTIVITIES	(31,748)	(95,797)
Effect of exchange rate changes on cash and cash equivalents	583	(280)
Increase (decrease) in cash and cash equivalents	41,764	(49,057)
Cash and cash equivalents at beginning of period	114,520	163,944
Cash and cash equivalents at end of period	$ 156,284	$ 114,887