Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 25, 2010	Dec. 26, 2009
OPERATING ACTIVITIES
Net income	$ 112,945	$ 86,582	$ 69,950
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of operating property and intangible assets	25,814	24,804	23,528
Non-cash interest charges	218	219	218
Provisions for losses on trade and other accounts receivable	7,804	3,916	7,986
Losses (gains) on sales/disposals of operating property, net	(266)	1,058	(55)
Deferred income taxes, net	10,071	525	2,419
Stock-based compensation	5,012	4,769	4,968
Changes in operating assets and liabilities:
Decrease (increase) in trade and other accounts receivable	(98,151)	(38,206)	32,780
Decrease (increase) in other assets	1,871	(1,752)	8,068
Increase (decrease) in accounts payable	26,010	16,267	(1,634)
Increase (decrease) in other liabilities	(5,729)	11,200	(13,748)
Increase (decrease) in insurance claims	32,435	(624)	10,484
NET CASH PROVIDED BY OPERATING ACTIVITIES	118,034	108,758	144,964
INVESTING ACTIVITIES
Net change in other short-term investments		1,730	28,024
Sales and maturities of investments	67,174	39,187	15,932
Purchases of investments	(58,413)	(65,818)	(49,965)
Purchases of operating property	(4,337)	(27,505)	(2,715)
Proceeds from sales of operating property	4,385	1,686	841
Consideration paid for acquisitions			(14,888)
NET CASH PROVIDED (USED) BY INVESTING ACTIVITIES	8,809	(50,720)	(22,771)
FINANCING ACTIVITIES
Increase (decrease) in cash overdraft	1,028	(4,042)	(3,146)
Dividends paid	(9,983)	(9,422)	(8,686)
Proceeds from exercises of stock options	923	1,660	1,128
Excess (shortfall) tax effect on stock option exercises	(683)	1,580	773
Borrowings on revolving credit facility	10,000	40,000	40,000
Purchases of common stock	(50,450)	(102,736)	(55,757)
Capital contribution from noncontrolling interest			580
Principal payments on long-term debt and capital lease obligations	(33,313)	(26,273)	(110,817)
Purchase of noncontrolling interest	(8,000)
NET CASH USED BY FINANCING ACTIVITIES	(90,478)	(99,233)	(135,925)
Effect of exchange rate changes on cash and cash equivalents	(171)	182	547
Increase (decrease) in cash and cash equivalents	36,194	(41,013)	(13,185)
Cash and cash equivalents at beginning of period	44,706	85,719	98,904
Cash and cash equivalents at end of period	$ 80,900	$ 44,706	$ 85,719