Fair Value of Financial Instruments - Narrative (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Option, Quantitative Disclosures [Line Items]
Assets	$ 282,327,000,000	$ 269,878,000,000
Liabilities	19,980,000,000	16,962,000,000
Fair Value, Nonrecurring
Fair Value, Option, Quantitative Disclosures [Line Items]
Assets	0	0
Liabilities	0	0
Commercial
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans with fair value option in non-accrual	0	0
Loans with fair value option, 90 days past due and still accruing	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

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- Definition

This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

+ References

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
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Fair value of financial and nonfinancial obligations.

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