Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Fixed-maturity securities, available-for-sale, at fair value	$ 10,275	$ 9,972
Common stock par value (per share)	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	137,928,552	158,306,661
Common stock, shares outstanding	137,928,552	158,306,661
Accumulated other comprehensive income, tax provision	$ 104	$ 159
Deferred equity compensation, shares	320,193	320,193