Interest and dividends on SAFS (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Debt Securities, Available-for-sale [Line Items]
Interest Income, Securities, Taxable	$ 219	$ 205	$ 435	$ 407
Interest Income, Securities, Tax Exempt	4	5	9	9
Interest and Dividend Income, Securities, Available-for-sale	$ 223	$ 210	$ 444	$ 416

Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on available-for-sale securities.

No definition available.

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

+ 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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