CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 27	$ 435	$ 1,062	$ 917
Other comprehensive income, net of reclassification adjustments:
Foreign currency translation gain (loss)	345	(87)	676	67
Unrealized gains (losses) on investments, net	(29)	281	(49)	304
Tax benefit (expense) on unrealized gains (losses) on investments, net	6	(80)	18	(101)
Unrealized gains (losses) on hedging activities, net	(64)	30	(98)	33
Tax benefit (expense) on unrealized gains (losses) on hedging activities, net	14	0	14	0
Other comprehensive income, net of tax	272	144	561	303
Comprehensive income	$ 299	$ 579	$ 1,623	$ 1,220

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 before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, on 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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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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