Legal Proceedings (Details Textuals) (USD $) In Millions, unless otherwise specified	Oct. 31, 2011
Legal Proceedings [Abstract]
Notice of proposed assessment for uncollected sales tax including interest and penalties	$ 73.8

The amount of the sales tax including penalties and interest raised on demand by the state authorities after performing audit.

No definition available.

Name:	cprt_SalesTaxOrderRaisedOnAuditIncludingPenaltiesAndInterestExpense
Namespace Prefix:	cprt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant