Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Other Comprehensive Income [Abstract]
Redeemable and mandatorily redeemable noncontrolling interests	$ 2.5	$ 2.0	$ 1.2

Net income loss attributable to redeemable and mandatorily redeemable non controlling interests.

No definition available.

Name:	woof_NetIncomeLossAttributableToRedeemableAndMandatorilyRedeemableNoncontrollingInterests
Namespace Prefix:	woof_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration