Investment Holding Level 4 Variable Interest Entities (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Variable Interest Entity [Line Items]
Percentage of Gross Unrealized Losses Depressed Less than Twenty Percent of Cost or Amortized Cost	94.00%
Variable Interest Entity, Nonconsolidated, Comparison of Carrying Amount of Assets and Liabilities to Maximum Loss Exposure [Abstract]
Variable Interest Entity, Nonconsolidated, Comparison of Carrying Amount of Assets and Liabilities to Maximum Loss Exposure	$ 820,000,000		$ 859,000,000
Variable Interest Entity, Commitments by Third Parties, Liquidity and Other Arrangements	494	497
Fixed Income Funds [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	$ 0		$ 0