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Derivatives - Gains/(Losses) on Derivatives Associated with Cash Flow Hedges and Mortgage Banking Hedges (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain/(loss) expected to be reclassified to earnings in the next twelve months | $ (20) | $ (20)
Cash Flow Hedge | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses), cash flow hedges | (43) | 33
Gain (loss) reclassified from AOCI into interest income | 13 | 11
Cash Flow Hedge | Hedging Instruments And Hedged Items | Interest Rate Swap |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses), cash flow hedges | (39) | 53
Mortgage Banking Hedges | Hedging Instruments And Hedged Items | Option contracts written |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | (1) | (1)
Mortgage Banking Hedges | Hedging Instruments And Hedged Items | Forward contracts written |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | $ 0 | $ (1)

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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480870/815-30-50-1 + 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 -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A + Details
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- Definition Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4C -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4C Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480627/815-20-45-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A + Details
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