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				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 25,005	$ 26,200	$ 23,861	$ 24,431	$ 26,200	$ 24,431
Other comprehensive income (loss) before reclassifications					(652)	411
Amounts reclassified into (out of) earnings					43	35
Other comprehensive income (loss)	(4)	(605)	490	(44)	(609)	446
Ending balance	25,167	25,005	24,873	23,861	25,167	24,873
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(418)	187	(920)	(876)	187	(876)
Other comprehensive income (loss)	(4)	(605)	490	(44)
Ending balance	(422)	(418)	(430)	(920)	(422)	(430)
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					(37)	103
Amounts reclassified into (out of) earnings					33	20
Other comprehensive income (loss)					(4)	123
Ending balance	53		53		53	53
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					(464)	456
Amounts reclassified into (out of) earnings					0	1
Other comprehensive income (loss)					(464)	457
Ending balance	384		866		384	866
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					111	22
Amounts reclassified into (out of) earnings					0	0
Other comprehensive income (loss)					111	22
Ending balance	(93)		68		(93)	68
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) earnings					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) earnings					10	14
Other comprehensive income (loss)					10	14
Ending balance	(168)		(173)		(168)	(173)
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					(262)	(170)
Amounts reclassified into (out of) earnings					0	0
Other comprehensive income (loss)					(262)	(170)
Ending balance	$ (596)		$ (1,242)		$ (596)	$ (1,242)