Noncontrolling Interests (Details Textuals) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Noncontrolling Interests (Textuals) [Abstract]
Percentage of ownership interest in partnership	50.10%
Mandatorily Redeemable Noncontrolling Interests included in other liabilities	$ 9,765	$ 11,047	$ 9,426	$ 3,111

Mandatorily Redeemable Noncontrolling Interests included in other liabilities.

No definition available.

Name:	woof_MandatorilyRedeemableNoncontrollingInterestsIncludedInOtherLiabilities
Namespace Prefix:	woof_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant