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Commitments and Contingencies (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 CAD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded to Other Party		$ 10
Litigation Settlement, Expense	$ 0	5	$ 0	$ 4,009,000
Percentage of defense costs which will be covered by insurance	50.00%
Insurance proceeds			$ 200,000	300,000
Estimated Litigation Liability, Current				$ 4,000,000.0
First Lawsuit By A G F
Loss Contingencies [Line Items]
Lawsuit filing date	On August 3, 2012, AGF Management Limited and AGF Investments Inc. (together “AGF”) filed a lawsuit in the Ontario Superior Court of Justice against Westwood, certain Westwood employees and the executive recruiting firm of Warren International, LLC (“Warren”).
Second Lawsuit by AGF
Loss Contingencies [Line Items]
Lawsuit filing date	November 6, 2012, AGF filed a second lawsuit against Westwood, Westwood Management and an employee of a Westwood subsidiary
Insurance Settlement [Member]
Loss Contingencies [Line Items]
Insurance proceeds	$ 4,000,000.0
Loss contingency, receivable		$ 5			$ 4,000,000.0