CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) [Abstract]
Revenues	$ 597,281	$ 438,065	$ 416,613
Cost of services	397,176	288,609	280,245
Gross profit	200,105	149,456	136,368
Selling, general and administrative expenses	155,706	130,830	121,141
Impairment of goodwill	0	15,399	0
Operating income	44,399	3,227	15,227
Interest expense	(2,975)	(8,309)	(6,612)
Interest income	39	141	170
Income (loss) before income taxes	41,463	(4,941)	8,785
Provision for income taxes	17,166	4,956	4,078
Net income (loss)	24,297	(9,897)	4,707
Earnings (loss) per share:
Basic	$ 0.66	$ (0.27)	$ 0.13
Diluted	$ 0.64	$ (0.27)	$ 0.13
Number of shares and share equivalents used to calculate earnings (loss) per share:
Basic	36,876	36,429	36,011
Diluted	37,758	36,429	36,335
Reconciliation of net income (loss) to comprehensive income (loss):
Net income (loss)	24,297	(9,897)	4,707
Changes in fair value of derivative, net of income tax of $227	(380)
Foreign currency translation adjustment	(1,662)	(1,122)	326
Comprehensive income (loss)	$ 22,255	$ (11,019)	$ 5,033

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.