Consolidated Statements of Cash Flows (unaudited) (USD $)	6 Months Ended
	Jun. 25, 2013	Jun. 26, 2012
Cash flows from operations:
Net income	$ 99,159,000	$ 85,321,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	49,632,000	43,462,000
Stock-based compensation expense	5,145,000	4,354,000
Excess tax benefit from exercise of stock options	(496,000)	(2,096,000)
Deferred income taxes	15,530,000	(3,206,000)
Other	824,000	1,116,000
Changes in operating assets and liabilities, excluding the effect of acquisitions and dispositions:
Trade and other accounts receivable, net	12,706,000	20,622,000
Inventories	1,044,000	488,000
Prepaid expenses and other	6,537,000	470,000
Deposits and other	763,000	38,000
Accounts payable	146,000	(2,310,000)
Accrued expenses	(42,579,000)	(3,223,000)
Deferred rent	2,091,000	2,607,000
Other long-term liabilities	(4,468,000)	(2,465,000)
Net cash provided by operating activities	146,034,000	145,178,000
Cash flows from investing activities:
Additions to property and equipment	(81,502,000)	(64,697,000)
Acquisitions, net of cash acquired	(2,446,000.000)	(47,951,000)
Purchases of investments	(97,919,000)	0
Net cash used in investing activities	(181,867,000)	(112,648,000)
Cash flows from financing activities:
Repurchase of common stock	(20,363,000)	(5,287,000)
Exercise of employee stock options	283,000	2,675,000
Excess tax benefit from exercise of stock options	496,000	2,096,000
Proceeds from issuance of common stock under employee benefit plans	1,414,000	1,145,000
Net cash provided by (used in) financing activities	(18,170,000)	629,000
Net increase (decrease) in cash and cash equivalents	(54,003,000)	33,159,000
Cash and cash equivalents at beginning of period	297,141,000	222,640,000
Cash and cash equivalents at end of period	$ 243,138,000	$ 255,799,000