Summary of Significant Accounting Policies (Details 7) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Calculation of Basic and Diluted Earnings per Share
Net income attributable to VCA Antech, Inc.	$ (58,051)	$ 34,037	$ 34,320	$ 35,245	$ (3,215)	$ 30,169	$ 39,612	$ 28,839	$ 45,551	$ 95,405	$ 110,243
Weighted-average common shares outstanding:
Basic									87,681	86,606	86,049
Effect of dilutive potential common stock:
Stock options									479	560	753
Nonvested shares									511	228	249
Diluted									88,671	87,394	87,051
Basic earnings per common share	$ (0.66)	$ 0.39	$ 0.39	$ 0.41	$ (0.04)	$ 0.35	$ 0.46	$ 0.33	$ 0.52	$ 1.10	$ 1.28
Diluted earnings per common share	$ (0.66)	$ 0.38	$ 0.39	$ 0.40	$ (0.04)	$ 0.35	$ 0.45	$ 0.33	$ 0.51	$ 1.09	$ 1.27