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Derivatives - Notional and Fair Value of Mortgage Banking Hedges (Details) - Mortgage Banking Hedges - Hedged Items - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Option contracts written |  |
Derivative [Line Items] |  |
Notional | $ 419 | $ 667
Assets | 7 | 20
Liabilities | 0 | 0
Forward contracts purchased |  |
Derivative [Line Items] |  |
Notional | 522 | 725
Assets | 3 | 0
Liabilities | $ 0 | $ 6

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- Definition Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations. + References No definition available. + Details
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- Definition Aggregate fair value of all derivative liabilities designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations. + References No definition available. + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959 + Details
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