Commitments Contingencies and Guarantees (Commitments to Fund Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Limited Partner [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	$ 263,163	$ 254,314
Commercial Loan [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	86,325	33,850
Bank Loan Obligations [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	48,686	52,859
Equity Release Mortgages [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	$ 8,504	$ 8,549