Condensed Financial Information of Registrant - Condensed Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Statements of Income
Revenue	$ 643,081	$ 656,854	$ 653,489	$ 563,439	$ 533,720	$ 551,717	$ 548,785	$ 449,453	$ 2,516,863	$ 2,133,675	$ 1,918,483
Direct costs									1,924,799	1,623,604	1,473,842
Gross profit	134,759	156,577	163,948	136,780	117,696	137,666	140,847	113,862	592,064	510,071	444,641
Selling, general and administrative expense									204,724	183,995	171,506
Net loss (gain) on sale or disposal of assets									1,006	829	(1,152)
Operating income (loss)	77,218	106,998	116,029	86,089	66,381	97,079	97,181	69,129	386,334	329,770	247,268
Income before provision for income taxes									353,183	351,641	227,561
Provision for income taxes									135,780	135,543	86,878
Net income	42,476	60,779	66,426	47,722	64,154	56,468	55,923	39,553	217,403	216,098	140,683
Net income attributable to noncontrolling interests									8,207	5,049	5,245
Net income attributable to VCA Inc.	$ 40,688	$ 58,231	$ 64,050	$ 46,227	$ 63,595	$ 54,854	$ 54,299	$ 38,301	209,196	211,049	135,438
Parent Company
Condensed Statements of Income
Revenue									0	0	0
Direct costs									0	0	0
Gross profit									0	0	0
Selling, general and administrative expense									0	0	0
Net loss (gain) on sale or disposal of assets									0	0	0
Operating income (loss)									0	0	0
Interest income, net									0	0	0
Equity interest in income of subsidiaries									209,196	211,049	135,438
Income before provision for income taxes									209,196	211,049	135,438
Provision for income taxes									0	0	0
Net income									209,196	211,049	135,438
Net income attributable to noncontrolling interests									0	0	0
Net income attributable to VCA Inc.									$ 209,196	$ 211,049	$ 135,438