Condensed Consolidated Statements Of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income	$ 430us-gaap_NetIncomeLoss	$ 368us-gaap_NetIncomeLoss
Other comprehensive income:
Change in gross unrealized investment gains/losses	14	108
Effect of income taxes	(5)	(39)
Total change in unrealized investment gains/losses, net of tax	9	69
Reclassification adjustment for net realized gains included in investment income	(9)	(1)
Effect of income taxes	4	0
Total reclassification adjustment, net of tax	(5)	(1)
Other comprehensive income, net of tax	4	68
Comprehensive income	$ 434us-gaap_ComprehensiveIncomeNetOfTax	$ 436us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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