Variable Interest Entities (Fair Value Unobservable Inputs) (Details 3) - Consolidated investment entities [Member] $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) $ / ft²	Dec. 31, 2016 USD ($)
Summary of the significant unobservable inputs
Debt	$ 6,630	$ 2,319	[1]
Property Funds [Member] | Minimum [Member] | Discounted cash flow/market comparables [Member]
Summary of the significant unobservable inputs
Equivalent yield	2.60%
Expected rental value (per square foot) | $ / ft²	3
Property Funds [Member] | Maximum [Member] | Discounted cash flow/market comparables [Member]
Summary of the significant unobservable inputs
Equivalent yield	11.50%
Expected rental value (per square foot) | $ / ft²	159
Property Funds [Member] | Weighted Average [Member] | Discounted cash flow/market comparables [Member]
Summary of the significant unobservable inputs
Equivalent yield	5.80%
Expected rental value (per square foot) | $ / ft²	51
CLO Debt [Member] | Minimum [Member] | Discounted cash flow valuation technique [Member]
Summary of the significant unobservable inputs
Annual default rate	2.50%
Discount rate	2.00%
Constant prepayment rate	5.00%
Loss recovery	36.40%
CLO Debt [Member] | Maximum [Member] | Discounted cash flow valuation technique [Member]
Summary of the significant unobservable inputs
Discount rate	11.80%
Constant prepayment rate	10.00%
Loss recovery	63.60%
CLO Debt [Member] | Weighted Average [Member] | Discounted cash flow valuation technique [Member]
Summary of the significant unobservable inputs
Discount rate	3.40%
Constant prepayment rate	9.90%
Loss recovery	62.90%
Recurring basis [Member]
Summary of the significant unobservable inputs
Debt	$ 6,630	$ 2,319	[2]
Level 3 [Member] | Recurring basis [Member]
Summary of the significant unobservable inputs
Debt	6,630
Level 3 [Member] | Recurring basis [Member] | Property Funds [Member]
Summary of the significant unobservable inputs
Other Assets, Fair Value Disclosure	$ 2,060

[1] As the Company elected the measurement alternative effective January 1, 2016, the carrying value of the CLOs’ debt is set equal to the fair value of the CLOs’ assets. See Note 3 and above for additional discussion on the measurement alternative. The estimated fair value of the CLOs’ debt was $2.3 billion at December 31, 2016.

[2] As the Company elected the measurement alternative effective January 1, 2016, the carrying value of the CLOs’ debt is set equal to the fair value of the CLOs’ assets. See Note 3 and below for additional discussion on the measurement alternative. The estimated fair value of the CLOs’ debt was $2.3 billion at December 31, 2016.