Variable Interest Entities (Fair Value Unobservable Inputs) (Details 3) - Consolidated investment entities [Member] $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) $ / ft²	Mar. 31, 2016 USD ($)	[1]
Summary of the significant unobservable inputs
Debt	$ 6,630	$ 2,673
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
Debt [Member] | Minimum [Member] | Discounted cash flow [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%
Debt [Member] | Maximum [Member] | Discounted cash flow [Member]
Summary of the significant unobservable inputs
Discount rate	11.80%
Constant prepayment rate	10.00%
Loss recovery	63.60%
Debt [Member] | Weighted average [Member] | Discounted cash flow [Member]
Summary of the significant unobservable inputs
Discount rate	3.40%
Constant prepayment rate	9.90%
Loss recovery	62.90%
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	2,060
Level 3 [Member] | Recurring basis [Member] | Debt [Member]
Summary of the significant unobservable inputs
Debt	$ 6,630

[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 2 and above for additional discussion on the measurement alternative. The estimated fair value of the CLOs’ debt was $2.7 billion at March 31, 2016.