Shareholders' Equity - Schedule of Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Net unrealized gains (losses) on cash flow hedges	$ 57	$ (70)	$ (89)
Net unrealized gains (losses) on available-for-sale securities portfolio	936	426	(193)
Net unrealized gains (losses) related to reclassified available-for-sale securities	(55)	19	58
Net unrealized gains (losses) on available-for-sale securities	881	445	(135)
Net unrealized (losses) on available-for-sale securities designated in fair value hedges	(33)	(36)	(40)
Net unrealized gains (losses) on hedges of net investments in non-U.S. subsidiaries	(204)	46	16
Other-than-temporary impairment on held-to-maturity securities related to factors other than credit	(2)	(2)	(2)
Net unrealized (losses) on retirement plans	(178)	(187)	(143)
Foreign currency translation	(334)	(1,072)	(963)
Total	$ 187	$ (876)	$ (1,356)

Expected losses from other than temporary impairment on held to maturity securities.

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Net Unrealized Gains (Losses) on Available-for-sale Securities

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Net Unrealized Loss On Available For Sale Securities Designated In Fair Value Hedges

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Net Unrealized Loss on Hedges of net Investments

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Net Unrealized Loss Related To Reclassified Securities

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Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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