A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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

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

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Shareholders' Equity - Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 25,167	$ 25,005	$ 26,200	$ 24,873	$ 23,861	$ 24,431	$ 26,200	$ 24,431
Other comprehensive income (loss) before reclassifications							(830)	786
Amounts reclassified into (out of) accumulated other comprehensive loss							(39)	(21)
Other comprehensive income (loss)	(260)	(4)	(605)	319	490	(44)	(869)	765
Ending balance	27,314	25,167	25,005	25,558	24,873	23,861	27,314	25,558
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(422)	(418)	187	(430)	(920)	(876)	187	(876)
Other comprehensive income (loss)	(260)	(4)	(605)	319	490	(44)
Ending balance	(682)	$ (422)	(418)	(111)	$ (430)	(920)	(682)	(111)
Net Unrealized Gains (Losses) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			57			(70)	57	(70)
Other comprehensive income (loss) before reclassifications							35	189
Amounts reclassified into (out of) accumulated other comprehensive loss							(51)	(37)
Other comprehensive income (loss)							(16)	152
Ending balance	41			82			41	82
Net Unrealized Gains (Losses) on Available-for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			848			409	848	409
Other comprehensive income (loss) before reclassifications							(558)	462
Amounts reclassified into (out of) accumulated other comprehensive loss							0	1
Other comprehensive income (loss)							(558)	463
Ending balance	290			872			290	872
Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(204)			46	(204)	46
Other comprehensive income (loss) before reclassifications							222	(100)
Amounts reclassified into (out of) accumulated other comprehensive loss							0	0
Other comprehensive income (loss)							222	(100)
Ending balance	18			(54)			18	(54)
Other-Than-Temporary Impairment on Held-to-Maturity Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(2)			(2)	(2)	(2)
Other comprehensive income (loss) before reclassifications							0	0
Amounts reclassified into (out of) accumulated other comprehensive loss							0	0
Other comprehensive income (loss)							0	0
Ending balance	(2)			(2)			(2)	(2)
Net Unrealized Losses on Retirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(178)			(187)	(178)	(187)
Other comprehensive income (loss) before reclassifications							0	0
Amounts reclassified into (out of) accumulated other comprehensive loss							12	15
Other comprehensive income (loss)							12	15
Ending balance	(166)			(172)			(166)	(172)
Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ (334)			$ (1,072)	(334)	(1,072)
Other comprehensive income (loss) before reclassifications							(529)	235
Amounts reclassified into (out of) accumulated other comprehensive loss							0	0
Other comprehensive income (loss)							(529)	235
Ending balance	$ (863)			$ (837)			$ (863)	$ (837)