Acquisition and Transition Costs and Special Charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Acquisition and Transition Costs	$ 4,890	$ 5,828	$ 58
Special Charges	41,144	4,893	170
Goodwill, Impairment Loss	28,500	$ 0	$ 0
Special Charges [Member]
Business Acquisition [Line Items]
Charges from Restructuring of Investment	7,145
Separation Benefits and Costs for Termination of Contracts	2,151
Costs Associated with the Wind-down of US PE	3,348
Special Charges [Member] | Institutional Asset Management [Member]
Business Acquisition [Line Items]
Goodwill, Impairment Loss	$ 28,500