Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 50,935	$ 44,323	$ 37,992
Depreciation and amortization	15,797	14,791	10,801
Stock-based compensation	10,477	8,838	8,139
Provision for doubtful accounts	2,178	921	1,712
Tax benefit from exercise of stock options	(121)	(231)	(26)
Deferred income tax provision	2,244	1,992	1,210
Accounts receivable	2,730	(7,149)	3,105
Inventories	(735)	(16,522)	(2,556)
Prepaid expenses and other current assets	(6,131)	(1,532)	389
Deferred customer acquisition costs	(1,452)	0	0
Other assets	1,023	1,417	(1,184)
Accounts payable	(71)	944	(1,085)
Accrued expenses	2,238	564	6,162
Income taxes payable	426	(366)	854
Deferred tuition revenue	(7,306)	1,826	1,839
Deferred revenue	1,050	0	0
Deferred rent	(92)	455	(758)
Gift certificate liability	1,336	1,483	(1,560)
Net cash provided by operating activities	74,526	51,754	65,034
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(13,560)	(7,022)	(2,539)
Acquisitions, net of cash acquired	(194,276)	0	(89,967)
Post-closing working capital adjustment related to acquisitions	0	3,895	0
Net cash used in investing activities	(207,836)	(3,127)	(92,506)
CASH FLOWS FROM FINANCING ACTIVITIES:
Purchase of treasury shares	(12,455)	(6,621)	(2,661)
Proceeds from long-term debt	175,000	0	60,500
Payments for long-term debt	(25,000)	(35,500)	(6,000)
Payments of debt issuance costs	(4,978)	(156)	(3,045)
Payment of contingent consideration	(1,500)
Tax benefit from exercise of stock options	121	231	26
Proceeds from share option exercises	2,678	1,759	1,124
Net cash provided by (used in) financing activities	133,866	(40,287)	49,944
EFFECT OF EXCHANGE RATE CHANGES ON CASH	358	540	(193)
NET INCREASE IN CASH AND CASH EQUIVALENTS	914	8,880	22,279
CASH AND CASH EQUIVALENTS, Beginning of year	61,731	52,851	30,572
CASH AND CASH EQUIVALENTS, End of year	62,645	61,731	52,851
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Interest	1,364	1,993	150
Income taxes	4,126	6,001	2,550
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING ACTIVITY:
Common stock issued in a business acquisition	$ 5,660