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Derivatives - Gains/(Losses) on Derivatives Associated with Mortgage Banking Hedges (Details) - Mortgage Banking Hedges - Hedged Items - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Option contracts written |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Gains (losses) on derivative instruments | $ 4 | $ (3) | $ 5 | $ (12)
Forward contracts written |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Gains (losses) on derivative instruments | 6 | 0 | 33 | 0
Forward contracts purchased |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Gains (losses) on derivative instruments | $ 0 | $ (2) | $ 0 | $ 10

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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. + Details
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 + Details
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