Debt Securities Available for Sale - Weighted average yield and contractual maturities of debt securities AFS - Parenthetical (Details) - Debt securities available-for-sale - USD ($) $ in Billions	Dec. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Pledged Financial Instruments, Not Separately Reported, Securities	$ 18.2	$ 12.2
Pledged Financial Instruments, Not Separately Reported, Securities for Other Debt Facilities	$ 16.9	$ 10.9

The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for debt facilities other than FHLB loans, repurchase agreements and letter of credit arrangements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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