Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 201	$ 42
Unrealized holding gains (losses) arising during the period on:
Investments with no other-than-temporary impairment, net of tax provision (benefit) of $1 and $41	18	94
Investments with other-than-temporary impairment, net of tax provision (benefit) of $(2) and $3	(2)	8
Unrealized holding gains (losses) arising during the period, net of tax	16	102
Less: reclassification adjustment for gains (losses) included in net income (loss), net of tax provision (benefit) of $6 and $(1)	10	(2)
Change in net unrealized gains on investments	6	104
Other, net of tax provision	(6)	0
Other comprehensive income (loss)	0	104
Comprehensive income (loss)	$ 201	$ 146