Loans and Leases - Narrative (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
Mar. 27, 2023	Jun. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Receivables [Abstract]
Financing receivable, accrued interest receivable		$ 601.0	$ 601.0	$ 203.0
Financing receivable, amortization of purchase discount		$ 243.0	$ 260.0
Financing receivable, threshold period past due		30 days	30 days
Other real estate owned		$ 64.0	$ 64.0	47.0
Financing receivable, troubled debt restructuring, commitment to lend		$ 12.0	$ 12.0	$ 1.5
SVB \| FDIC Credit Facility
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt instrument, term	5 years
FDIC advances, maximum amount available	$ 70,000.0

Federal Deposit Insurance Corporation, Advances, General Debt Obligations, Maximum Amount Available

No definition available.

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- Definition

Financing Receivable, Amortization Of Purchase Discount

+ References

No definition available.

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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.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3A

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- Definition

Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-14

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- Definition

Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 36
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-36

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 40
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481746/310-40-50-1

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- Definition

Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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- References

No definition available.

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