Consolidated Statements of Shareholders' 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
Shareholders' net income	$ 806	$ 813	$ 1,721	$ 1,411
Shareholders' other comprehensive income (loss), net of tax:
Net unrealized appreciation (depreciation), securities	(141)	67	(420)	74
Net unrealized appreciation (depreciation), derivatives	(8)	0	(13)	(3)
Net translation of foreign currencies	(152)	27	(107)	139
Postretirement benefits liability adjustment	5	12	18	26
Shareholders' other comprehensive income (loss), net of tax	(296)	106	(522)	236
Shareholders' comprehensive income (loss)	$ 510	$ 919	$ 1,199	$ 1,647

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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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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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, attributable to parent entity.

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