Commitments and Contingencies - Pledged Assets (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total loans and leases	$ 327,673	$ 325,991
Asset Pledged as Collateral
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Securities, fair value	71,890	38,012
Federal Reserve Bank Advances [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	53,291	49,250
Federal Reserve Bank Advances [Member] \| Asset Pledged as Collateral
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total loans and leases	75,018	71,234
FHLB Advances
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	24,678	20,770
FHLB Advances \| Asset Pledged as Collateral
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total loans and leases	$ 70,766	$ 68,988

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
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Amount of investment in marketable security.

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-Section S99
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