Consolidated Statement Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating activities
Net income	$ 214,945	$ 178,981	$ 126,845
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	74,938	68,921	61,308
Deferred income tax provision	11,319	10,064	8,282
Increase in valuation allowance	616	415	141
Loss on disposal of assets	5,806	6,296	5,956
Bad debt allowance	239	(151)	(245)
Stock-based compensation expense	41,382	21,381	14,992
Excess tax benefit on stock-based compensation	(38,786)	(14,526)	(10,435)
Other	2,501		222
Changes in operating assets and liabilities:
Accounts receivable	(2,970)	(743)	(875)
Inventory	(1,816)	(1,481)	(825)
Prepaid expenses and other current assets	(5,399)	(1,632)	(2,613)
Other assets	(7,350)	(8,956)	374
Accounts payable	9,432	6,989	1,435
Accrued liabilities	17,451	16,607	19,804
Income tax receivable/payable	66,555	(13,209)	14,927
Deferred rent	19,624	17,261	19,386
Other long-term liabilities	2,609	2,974	1,994
Net cash provided by operating activities	411,096	289,191	260,673
Investing activities
Purchases of leasehold improvements, property and equipment	(151,147)	(113,215)	(117,198)
Acquisition of interests in equity method investment	(586)	(1,900)
Purchases of investments	(183,251)	(125,000)	(50,000)
Maturities of investments	124,766	50,234	99,990
Net cash used in investing activities	(210,218)	(189,881)	(67,208)
Financing activities
Acquisition of treasury stock	(63,508)	(126,602)	(84,089)
Proceeds from option exercises	574	17,650	11,793
Excess tax benefit on stock-based compensation	38,786	14,526	10,435
Payments on deemed landlord financing	(120)	(96)	(82)
Net cash used in financing activities	(24,268)	(94,522)	(61,943)
Effect of exchange rate changes on cash and cash equivalents	(205)	484
Net change in cash and cash equivalents	176,405	5,272	131,522
Cash and cash equivalents at beginning of year	224,838	219,566	88,044
Cash and cash equivalents at end of year	401,243	224,838	219,566
Supplemental disclosures of cash flow information
Income taxes paid	56,270	112,150	53,644
(Increase) decrease in purchases of leasehold improvements, property and equipment accrued in accounts payable	$ (3,249)	$ (1,480)	$ 95