Noncontrolling Interests (Details Textuals) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Noncontrolling Interests (Textuals) [Abstract]
Percentage of ownership interest in partnership	50.10%
Mandatorily Redeemable Noncontrolling Interests included in other liabilities	$ 11.7	$ 3.1

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