Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 2,242	$ 2,593	$ 2,156
Other comprehensive income (loss), net of related taxes:
Foreign currency translation, net of related taxes	(9)	(67)	900
Net unrealized gains (losses) on available-for-sale securities, net of reclassification adjustment and net of related taxes	545	(302)	367
Net unrealized gains (losses) on available-for-sale securities designated in fair value hedges, net of related taxes	18	24	22
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit, net of related taxes	1	4	3
Net unrealized gains (losses) on cash flow hedges, net of related taxes	25	(33)	(285)
Net unrealized gains (losses) on retirement plans, net of related taxes	(16)	27	24
Other comprehensive income (loss)	564	(347)	1,031
Total comprehensive income	$ 2,806	$ 2,246	$ 3,187

Other Comprehensive Income (Loss), Expected Losses From OTTI on HTM Securities Not From Credit, Net of Taxes

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Other Comprehensive Income (Loss), Securities, Available-For-Sale, Designated In Fair Value Hedges, Unrealized Holding Gain (Loss) Arising During Period, After Tax

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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, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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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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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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