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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, 2025 | Mar. 31, 2024
Derivative Instruments, Gain (Loss) [Line Items] |  |
Loss expected to be reclassified to earnings in the next twelve months | $ (13) | $ (13)
Cash Flow Hedge | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses), cash flow hedges | 18 | (43)
Gain (loss) reclassified from AOCI into interest income | 9 | 13
Interest Rate Swap | Cash Flow Hedge | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses), cash flow hedges | 36 | (39)
Option contracts written | Mortgage Banking Hedges | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | (1) | (1)
Forward contracts written | Mortgage Banking Hedges | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | $ 1 | $ 0

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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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- Definition Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as 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 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-15 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 4C -Subparagraph (c) -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4C + Details
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