Loans Receivable and Allowance for Credit Losses - Allowance for Credit Losses Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($) qtr	Jun. 30, 2023 qtr	Dec. 31, 2022 USD ($)
Financing Receivable Allowance for Credit Losses
Life time loss rate, period span \| qtr	8
Allowance for credit losses \| $	$ 689.1		$ 621.9
Increase in allowance for credit losses \| $	$ 67.2
Commercial and industrial (“C&I”)
Financing Receivable Allowance for Credit Losses
Life time loss rate, period span \| qtr	8	11

Financing Receivable And Off Balance Sheet Credit Loss Allowance

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- Definition

Financing Receivable And Off Balance Sheet Credit Loss Allowance, Period Increase (Decrease)

+ References

No definition available.

+ Details

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- Definition

Reasonable and Supportable Forecast Period, Life Time Loss Rate, Period

+ References

No definition available.

+ 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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