Condensed Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Revenue	$ 608,351	$ 535,177	$ 1,210,812	$ 1,067,618
Cost of revenue	410,811	355,635	811,206	711,317
Gross profit	197,540	179,542	399,606	356,301
Operating expenses:
Selling, general and administrative	137,068	121,668	283,302	241,665
Depreciation and amortization	22,071	12,718	42,160	24,428
Total operating expenses	159,139	134,386	325,462	266,093
Income from operations	38,401	45,156	74,144	90,208
Interest expense, net, and other	11,443	6,065	22,497	11,738
Income before income taxes	26,958	39,091	51,647	78,470
Income tax expense	4,633	10,222	16,357	15,479
Net income	22,325	28,869	35,290	62,991
Other comprehensive loss:
Foreign currency translation and other	(58)	(89)	(105)	(190)
Other comprehensive loss	(58)	(89)	(105)	(190)
Comprehensive income	$ 22,267	$ 28,780	$ 35,185	$ 62,801
Net income per common share:
Basic (in dollars per share)	$ 0.47	$ 0.62	$ 0.74	$ 1.35
Diluted (in dollars per share)	$ 0.47	$ 0.61	$ 0.74	$ 1.32
Weighted average common shares outstanding:
Basic (shares)	47,383	46,644	47,371	46,713
Diluted (shares)	47,562	47,424	47,623	47,597