Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Commitments and Contingencies Disclosure [Abstract]
Settlement, litigation and other related charges	$ 3,512	$ 26,093	$ 26,131	$ 33,296

Amount charged against earnings for litigation related settlements and professional expenses primarily in connection with specifically identified legal proceedings.

No definition available.

Name:	ocr_LitigationAndOtherProfessionalFees
Namespace Prefix:	ocr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration