Calculation of Earnings per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Calculation of Basic and Diluted Earnings per Share
Net income attributable to VCA Antech, Inc.	$ 30,485	$ 35,245
Weighted-average common shares outstanding:
Basic	88,400,000	86,984,000
Effect of dilutive potential common shares:
Stock options	284,000	560,000
Nonvested shares	695,000	511,000
Diluted	89,379,000	88,055,000
Basic earnings per share	$ 0.34	$ 0.41
Diluted earnings per share	$ 0.34	$ 0.40
Calculation of Earnings per Share (Textuals) [Abstract]
Potential common shares excluded from the computation of diluted earnings per share	497,826	1,067,063