Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Settlements, litigations and other related charges	$ 22,619	$ 7,203

Settlements, litigations and other related charges

No definition available.

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