Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Net service revenue	$ 252,078	$ 248,997
Reimbursable out-of-pocket expenses	129,840	164,090
Total revenue	381,918	413,087
Costs and operating expenses:
Direct costs (exclusive of depreciation and amortization)	154,835	152,058
Reimbursable out-of-pocket expenses	129,840	164,090
Selling, general, and administrative	44,934	43,479
Restructuring, CEO transition, and other costs	1,927	6,038
Transaction expenses	2	561
Depreciation	6,164	4,892
Amortization	9,464	9,461
Total operating expenses	347,166	380,579
Income from operations	34,752	32,508
Other (expense) income, net:
Interest income	112	34
Interest expense	(3,100)	(3,004)
Other (expense) income, net	(3,457)	(5,117)
Total other (expense) income, net	(6,445)	(8,087)
Income before provision for income taxes	28,307	24,421
Income tax expense	(7,120)	(7,016)
Net income	$ 21,187	$ 17,405
Earnings per share:
Basic (USD per share)	$ 0.39	$ 0.32
Diluted (USD per share)	$ 0.38	$ 0.31
Weighted average common shares outstanding:
Basic (shares)	54,015	53,955
Diluted (shares)	55,123	55,862