Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 676	$ 579	$ 1,651	$ 1,274
Changes in:
Unrealized net capital gains and losses	(133)	270	(698)	473
Unrealized foreign currency translation adjustments	(7)	11	(11)	8
Unrecognized pension and other postretirement benefit cost	22	18	45	37
Other comprehensive (loss) income, after-tax	(118)	299	(664)	518
Comprehensive income	$ 558	$ 878	$ 987	$ 1,792

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Net of tax amount of the appreciation (loss) in the value of unsold available-for-sale securities. Includes amounts related to other than temporary impairment (OTTI) losses.

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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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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