Calculation of Earnings per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Calculation of Basic and Diluted Earnings per Share
Net income attributable to VCA Antech, Inc.	$ 35,245	$ 28,839
Weighted-average common shares outstanding:
Basic	86,984,000	86,355,000
Effect of dilutive potential common shares:
Stock options	560,000	690,000
Nonvested shares	511,000	200,000
Diluted	88,055,000	87,245,000
Basic earnings per share	$ 0.41	$ 0.33
Diluted earnings per share	$ 0.40	$ 0.33
Calculation of Earnings per Share (Textuals) [Abstract]
Potential common shares excluded from the computation of diluted earnings per share	1,067,063	46,270