Regulatory Requirements (Details)	12 Months Ended
	Dec. 31, 2015 USD ($)
Oppenheimer
Regulatory Capital Requirements [Line Items]
Required percentage of net capital to aggregate customer-related debit items	2.00%
Net capital	$ 144,800,000
Actual percentage of net capital to aggregate customer-related debit items	12.34%
Excess capital	$ 121,400,000
Freedom
Regulatory Capital Requirements [Line Items]
Net capital	5,800,000
Minimum net capital required (in excess)	100,000
Net capital in excess of minimum required	$ 5,700,000
Percentage of net capital to aggregate indebtedness	6.67%
Oppenheimer Europe Ltd
Regulatory Capital Requirements [Line Items]
Common equity tier 1 ratio	12.32%
Common equity tier 1 ratio required	4.50%
Tier 1 capital ratio	12.32%
Tier 1 capital ratio required	6.00%
Total capital ratio	13.75%
Total capital ratio required	8.00%
Oppenheimer Investments Asia Ltd.
Regulatory Capital Requirements [Line Items]
Net capital	$ 2,500,000
Net capital in excess of minimum required	2,100,000
Regulatory capital required to be maintained	$ 387,000