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Derivatives - Schedule of Gains/(Losses) on Derivatives Associated with Cash Flow Hedges and Mortgage Banking Hedges (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain/(loss) expected to be reclassified to earnings in the next twelve months | $ (9) |  |
Cash Flow Hedges | Hedging Instruments And Hedged Items |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss), cash flow hedges | 52 | $ 15 | $ (3)
Gain (loss) reclassified from AOCI into interest income | 47 | (129) | (7)
Cash Flow Hedges | Hedging Instruments And Hedged Items | Interest rate contracts |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss), cash flow hedges | 45 | 195 | 29
Mortgage Banking Hedges | Hedging Instruments And Hedged Items | Interest Rate Lock |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) on derivative instruments | 0 | 3 | 15
Mortgage Banking Hedges | Hedging Instruments And Hedged Items | Forward contracts written |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) on derivative instruments | $ 1 | $ 32 | $ 11

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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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