Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Share Capital	Share Capital Class A Stock	Contributed Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ 53,392		$ 41,776	$ 449,989	$ 165
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A non-voting common stock			$ 1,565
Repurchase of Class A non-voting common stock for cancellation			(8,400)
Net Income (Loss) Attributable to Parent	$ 27,518				27,518
Share-based expense				6,071
Vested employee share plan awards				(2,498)
Dividends paid					$ (4,408)
Currency translation adjustment	1,457					1,457
Dividends paid per share					$ 0.34
Stockholders' equity attributable to Oppenheimer Holdings Inc.		48,202		43,626	$ 470,693	1,089
Issuance of Class A non-voting common stock			403
Repurchase of Class A non-voting common stock for cancellation			(2,048)
Net Income (Loss) Attributable to Parent	3,949				3,949
Share-based expense				2,045
Vested employee share plan awards				(322)
Dividends paid					$ (1,543)
Currency translation adjustment	533					533
Dividends paid per share					$ 0.12
Stockholders' equity attributable to Oppenheimer Holdings Inc.	566,627	46,557		45,349	$ 473,099	1,622
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	566,627	46,557		45,349	473,099	1,622
Stockholders' equity attributable to Oppenheimer Holdings Inc.	592,722
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		46,557		47,406	496,998	1,761
Issuance of Class A non-voting common stock			7,644
Repurchase of Class A non-voting common stock for cancellation	(14,200)		(14,228)
Net Income (Loss) Attributable to Parent	41,106
Share-based expense				5,763
Vested employee share plan awards				(13,381)
Dividends paid					$ (4,597)
Currency translation adjustment	187					187
Dividends paid per share					$ 0.36
Stockholders' equity attributable to Oppenheimer Holdings Inc.		40,917		39,140	$ 519,376	1,704
Issuance of Class A non-voting common stock			1,018
Repurchase of Class A non-voting common stock for cancellation	(2,000)		$ (1,962)
Net Income (Loss) Attributable to Parent	15,639
Share-based expense				1,944
Vested employee share plan awards				(1,296)
Dividends paid					$ (1,508)
Currency translation adjustment	244					244
Dividends paid per share					$ 0.12
Stockholders' equity attributable to Oppenheimer Holdings Inc.	615,216	39,973		39,788	$ 533,507	1,948
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 615,216	$ 39,973		$ 39,788	$ 533,507	$ 1,948