CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY AND NONCONTROLLING INTERESTS (unaudited) - USD ($) $ in Thousands	Total	Parent	Common Stock	Common Stock Class A Stock	Additional paid-in capital	Additional paid-in capital Class A Stock	Retained earnings		Accumulated other comprehensive income (loss)	Non-controlling interest
Balance at beginning of period at Dec. 31, 2024			$ 10		$ 29,733		$ 819,961		$ 691	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A non-voting common stock				$ 0		$ 6,199
Repurchase of Class A non-voting common stock for cancellation						(90)
Share-based expense					3,458
Vested employee share plan awards					(15,969)
Net income (loss)	$ 30,655						30,655	[1]		0
Dividends declared							(1,895)
Currency translation adjustment	(487)								(487)
Balance at end of period at Mar. 31, 2025	$ 872,266	$ 872,266	10		23,331		848,721		204	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends paid per share (in dollars per share)	$ 0.18
Balance at beginning of period at Dec. 31, 2024			10		29,733		819,961		691	0
Balance at end of period at Dec. 31, 2025	$ 997,029		10		32,703		947,413		3,697	13,206
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A non-voting common stock				$ 1		8,261
Repurchase of Class A non-voting common stock for cancellation						$ 0
Share-based expense					3,951
Vested employee share plan awards					(21,318)
Net income (loss)	(20,569)						(20,578)	[1]		9
Dividends declared							(1,927)
Currency translation adjustment	213								213
Balance at end of period at Mar. 31, 2026	$ 965,641	$ 952,426	$ 11		$ 23,597		$ 924,908		$ 3,910	$ 13,215
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends paid per share (in dollars per share)	$ 0.18

[1] (1) Attributable to Oppenheimer Holdings Inc.