Debt Securities, Available-for-sale, Change in Present Value, Accretion

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- Definition

Holding Companies with Outstanding Public Debt, Number

+ References

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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-Publisher FASB
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- Definition

Amount of 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of allowance for credit 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded.

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Business and Basis of Presentation Business and Basis of Presentation (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) Company	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Number of Holding Companies with outstanding public debt \| Company	2
Unrealized loss position	$ 9,501		$ 10,122
Amortized cost	9,343		9,639
Allowance for Credit Losses	(73)	$ (197)	0	$ (185)
Additions for credit losses on securities for which credit impairments were not previously recognized	2	$ 0
Cumulative Effect, Period Of Adoption, Adjustment [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Allowance for Credit Losses			(62)
PCD Accounting Model to PCI Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Additions for credit losses on securities for which credit impairments were not previously recognized	11
Change in present value, accretion	$ 1
PCD Accounting Model to PCI Securities [Member] \| Cumulative Effect, Period Of Adoption, Adjustment [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Unrealized loss position			248
Amortized cost			266
Allowance for Credit Losses			$ 62