CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues	$ 653,313	$ 608,088	$ 1,279,841	$ 1,190,128
Cost of services	440,376	406,002	868,760	800,260
Gross profit	212,937	202,086	411,081	389,868
Selling, general and administrative expenses	145,177	141,350	291,249	281,231
Amortization of intangible assets	8,299	10,032	16,763	20,176
Operating income	59,461	50,704	103,069	88,461
Interest expense	(6,067)	(7,959)	(14,568)	(16,984)
Income before income taxes	53,394	42,745	88,501	71,477
Provision for income taxes	20,158	16,732	32,883	28,116
Income from continuing operations	33,236	26,013	55,618	43,361
Income (loss) from discontinued operations, net of income taxes	(139)	(9)	(130)	44
Net income	$ 33,097	$ 26,004	$ 55,488	$ 43,405
Basic earnings per common share:
Continuing operations	$ 0.63	$ 0.49	$ 1.05	$ 0.81
Discontinued operations	0.00	0.00	0.00	0.00
Net income	0.63	0.49	1.05	0.81
Diluted earnings per common share:
Continuing operations	0.62	0.48	1.04	0.81
Discontinued operations	0.00	0.00	0.00	0.00
Net income	$ 0.62	$ 0.48	$ 1.04	$ 0.81
Number of shares and share equivalents used to calculate earnings per share:
Basic	52,823	53,422	52,741	53,284
Diluted	53,473	53,911	53,375	53,783
Reconciliation of net income to comprehensive income:
Net income	$ 33,097	$ 26,004	$ 55,488	$ 43,405
Foreign currency translation adjustment	3,143	(1,083)	3,845	260
Comprehensive income	$ 36,240	$ 24,921	$ 59,333	$ 43,665