Investments (Consolidated Variable Interest Entities) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Variable Interest Entity [Line Items]
Total Assets	$ 6,264	$ 8,558
Total Liabilities	2,218	3,684
Consolidated Securitization Entities [Member]
Variable Interest Entity [Line Items]
Total Assets	333	1,630
Total Liabilities	189	1,457
MRSC collateral financing arrangement [Member]
Variable Interest Entity [Line Items]
Total Assets	3,373	3,440
Total Liabilities	0	0
Operating joint venture [Member]
Variable Interest Entity [Line Items]
Total Assets	2,380	2,095
Total Liabilities	2,014	1,777
Other limited partnership interests [Member]
Variable Interest Entity [Line Items]
Total Assets	61	61
Total Liabilities	0	0
Real estate joint ventures [Member]
Variable Interest Entity [Line Items]
Total Assets	9	1,181
Total Liabilities	15	443
Other invested assets [Member]
Variable Interest Entity [Line Items]
Total Assets	59	82
Total Liabilities	0	7
Actively traded securities [Member]
Variable Interest Entity [Line Items]
Total Assets	49	69
Total Liabilities	$ 0	$ 0