Calculation of Earnings per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Calculation of Basic and Diluted Earnings per Share
Net income attributable to VCA Antech, Inc.	$ 30,169	$ 27,431	$ 98,620	$ 88,770
Weighted-average common shares outstanding:
Basic	86,697,000	86,086,000	86,531,000	85,985,000
Effect of dilutive potential common shares:
Stock options	445,000	632,000	593,000	812,000
Nonvested shares	111,000	246,000	169,000	201,000
Diluted	87,253,000	86,964,000	87,293,000	86,998,000
Basic earnings per share	$ 0.35	$ 0.32	$ 1.14	$ 1.03
Diluted earnings per share	$ 0.35	$ 0.32	$ 1.13	$ 1.02
Calculation of Earnings per Share (Textuals) [Abstract]
Potential common shares excluded from the computation of diluted earnings per share	2,104,547	1,162,389	1,139,567	13,919