Acquisitions - Schedules of Loans Acquired (Details) $ in Millions	Feb. 01, 2022 USD ($)
Business Acquisition [Line Items]
Certain Loans Acquired in Transfer Accounted for as Available-for-Sale Debt Securities, Accrued Interest	$ (18.1)
Purchase Price (Initial Fair Value)	623.3
Great Western Bank
Business Acquisition [Line Items]
Contractually required principal and interest payments	979.2
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Other-than-Temporary Impairment Charges, Credit Loss	238.7
Contractual cash flows not expected to be collected (“non-accretable discount”)	29.9
Purchase Price (Initial Fair Value)	623.3
Interest component of cash flows expected to be collected (“accretable discount”)	(69.2)
Fair value of acquired credit-impaired loans	682.8
Contractually required principal and interest payments	7,107.9
Contractual cash flows not expected to be collected	9.2
Fair value at acquisition	7,022.2
Certain Loans Acquired in Transfer Accounted for as Available-for-sale Debt Securities, Acquired, at Acquisition, at Fair Value	$ 722.4

Certain Loans Acquired in Transfer Accounted for as Available-for-Sale Debt Securities, Accrued Interest

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Loans Acquired in Transfer, Contractually Required Payments Receivable at Acquisition

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Loans Acquired in Transfer, Nonaccretable Difference

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Loans Acquired in Transfer at Acquisition Fair Value

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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.

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Fair value at acquisition of acquired loans accounted for as available-for-sale debt securities with evidence of deterioration of credit quality.

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Amount of expense to write-down the amortized cost basis of loans, after acquisition, to fair value when the decline in the fair value is determined to be other than temporary (OTTI) for loans accounted for as debt securities.

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The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of contractually required payments receivable at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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