Consolidated Statements of Changes in Equity (Deficit) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax	$ 3	$ 5
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax	(3)	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect	$ (1)	$ 1

Tax effect of plan amendments that occurred that has not been recognized in net periodic benefit cost.

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-Publisher FASB
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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580

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