CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues	$ 878,509	$ 653,313	$ 1,563,682	$ 1,279,841
Cost of services	614,663	440,376	1,082,099	868,760
Gross profit	263,846	212,937	481,583	411,081
Selling, general and administrative expenses	179,616	145,177	344,060	291,249
Amortization of intangible assets	18,548	8,299	26,149	16,763
Operating income	65,682	59,461	111,374	103,069
Interest expense	(20,573)	(6,067)	(27,118)	(14,568)
Income before income taxes	45,109	53,394	84,256	88,501
Provision for income taxes	11,508	20,158	21,415	32,883
Income from continuing operations	33,601	33,236	62,841	55,618
Loss from discontinued operations, net of income taxes	(40)	(139)	(188)	(130)
Net income	$ 33,561	$ 33,097	$ 62,653	$ 55,488
Earnings per share:
Basic	$ 0.64	$ 0.63	$ 1.20	$ 1.05
Diluted	$ 0.63	$ 0.62	$ 1.19	$ 1.04
Number of shares and share equivalents used to calculate earnings per share:
Basic	52,305	52,823	52,242	52,741
Diluted	53,010	53,473	52,920	53,375
Reconciliation of net income to comprehensive income:
Net income	$ 33,561	$ 33,097	$ 62,653	$ 55,488
Foreign currency translation adjustment	(2,635)	3,143	(1,160)	3,845
Comprehensive income	$ 30,926	$ 36,240	$ 61,493	$ 59,333