Equity Changes in AOCI (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Statutory corporate tax rate	21.00%	21.00%	21.00%
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	$ 14,608
Total other comprehensive loss	(15)	$ (191)	$ (348)
Ending balance	$ 25,259	$ 14,608

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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+ Details

- Definition

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.

+ References + Details