XML 54 R68.htm IDEA: XBRL DOCUMENT v2.4.0.8

Condensed Consolidating Financial Information - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2014
Condensed Financial Information Of Parent Company Only Disclosure [Abstract]
Interest owned by the holding company	100.00%

X

- Definition

The percentage of ownership the holding company owns the guarantors.

+ References

No definition available.

+ Details

Name:	opy_InterestOwnershipByHoldingCompany
Namespace Prefix:	opy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration