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Fair Value Measurements - Interest Rate Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
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Fixed-to-Floating Interest Rate Swap | Fair Value Hedging |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value hedge derivative instrument liabilities at fair value | $ 159 | $ 118
Forward Starting Interest Rate Swap | Cash Flow Hedge |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Cash flow hedge derivative instrument assets at fair value | $ 54 | $ 127

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- Definition Fair value of all asset derivatives designated as cash flow hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4B + Details
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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 Fair value as of the balance sheet date of all derivative liabilities designated as interest rate fair value hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4B + Details
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