Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Operating activities
Net income	$ 47,166	$ 26,178
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	16,022	18,449
Amortization of other intangible assets	11,517	11,186
Acquisition-related contingent consideration	(6,721)	(2,984)
Provision for doubtful accounts	7,478	7,027
Non-cash share-based compensation	17,046	17,805
Non-cash interest expense	1,349	3,887
Other	(197)	70
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, billed and unbilled	(58,827)	(50,190)
Notes receivable	(11,113)	(23,834)
Prepaid expenses and other assets	(1,485)	(4,363)
Accounts payable, accrued expenses and other	(1,354)	(1,216)
Income taxes	14,740	(17,108)
Accrued compensation	(10,467)	(43,081)
Billings in excess of services provided	(5,785)	886
Net cash provided by (used in) operating activities	19,369	(57,288)
Investing activities
Payments for acquisition of businesses, net of cash received	(40,512)	(21,550)
Purchases of property and equipment	(14,130)	(13,728)
Other	21	93
Net cash used in investing activities	(54,621)	(35,185)
Financing activities
Payments of long-term debt and capital lease obligations		(1,974)
Purchase and retirement of common stock	(28,758)
Net issuance of common stock under equity compensation plans	1,245	(840)
Other	(616)	(1,324)
Net cash provided by (used in) financing activities	(28,129)	(4,138)
Effect of exchange rate changes on cash and cash equivalents	(850)	(1,831)
Net decrease in cash and cash equivalents	(64,231)	(98,442)
Cash and cash equivalents, beginning of period	156,785	264,423
Cash and cash equivalents, end of period	92,554	165,981
Supplemental cash flow disclosures
Cash paid for interest	22,903	25,367
Cash paid for income taxes, net of refunds	18,446	31,230
Non-cash investing and financing activities:
Issuance of stock units under incentive compensation plans	3,005	3,079
Issuance of common stock to acquire businesses	$ 2,883