CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 21,712	$ 24,508	$ 74,041	$ 60,518
Other comprehensive income (loss), net of tax
Currency translation adjustment	451	271	2,110	(697)
Comprehensive income	22,163	24,779	76,151	59,821
Net loss attributable to noncontrolling interests	0	0	0	(310)
Comprehensive income attributable to Oppenheimer Holdings Inc.	$ 22,163	$ 24,779	$ 76,151	$ 60,131

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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