Fair Value of Assets and Liabilities (Details 5) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	$ (15)	$ 2
Total recurring Level 3 liabilities	(15)	(4)
Fair value, assets and liabilities gain (loss) included in earnings	(16)	(6)
Realized capital gains and losses
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date	(18)	(1)
Net investment income
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date	3	3
Interest credited to contractholder funds
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date	1	(4)
Contract benefits
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date	(16)
Gain (Loss) on Investments [Member]
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair value, assets and liabilities gain (loss) included in earnings	(30)	(2)
Contractholder funds: Derivatives embedded in life and annuity contracts
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 liabilities	(15)	(4)
Corporate
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	(2)	2
Equity securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	(12)	0
Free-standing derivatives, net
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	$ (1)	$ 0