Name:	opy_CommonEquityTierOneRatioRequiredUnderCrdFourth
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Common Equity Tier 1 Ratio calculated for capital adequacy purposes under the Capital Requirements Directive (DRD IV) in the European Union.

No definition available.

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Percentage of net capital to aggregate indebtedness.

No definition available.

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Required percentage of net capital to aggregate customer related debit items.

No definition available.

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Tier One Capital Ratio calculated for capital adequacy purposes under the Capital Requirements Directive (DRD IV) in the European Union.

No definition available.

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Tier One Capital Ratio required for capital adequacy purposes under the Capital Requirements Directive (DRD IV) in the European Union.

No definition available.

Name:	opy_TierOneCapitalRatioRequiredUnderCrdFourth
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Total Capital Ratio calculated for capital adequacy purposes under the Capital Requirements Directive (DRD IV) in the European Union.

No definition available.

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Total Capital Ratio Required for capital adequacy purposes under the Capital Requirements Directive (DRD IV) in the European Union.

No definition available.

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The amount of net capital in excess of the alternative minimum required net capital.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3-1

-Number 240

-Section 15c3-1

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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The amount of net capital in excess of the minimum required net capital.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3-1

-Number 240

-Section 15c3-1

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Amount of minimum net capital required to be maintained to engage in securities transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3-1

-Number 240

-Section 15c3-1

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Minimum amount of net capital required to be maintained by entity's broker-dealer subsidiary to engage in securities transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3-1

-Number 240

-Section 15c3-1

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Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3-1

-Number 240

-Section 15c3-1

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