Significant Accounting Policies - Impacts of COVID-19 (Details) $ in Millions		3 Months Ended
Jun. 01, 2020 USD ($)	Jun. 30, 2020 USD ($) customer
Paycheck Protection Program
Paycheck Protection Program ("PPP")
Loans outstanding		$ 746.4
Amortized cost of the loans outstanding		$ 729.3
New and existing customers \| customer		4,445
Loans outstanding, fees received		$ 25.0
Incurred incremental direct origination costs		4.9
Net interest income		3.0
5.25% fixed-to-floating rate notes due 2030 \| Subordinated debt
Impacts of COVID-19
Proceeds from public offering	$ 125.0	$ 125.0
Interest rate (as a percent)		5.25%

Represents the amortized cost of the loans outstanding related to the PPP (paycheck protection program).

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Represents the fees received related to the PPP (Paycheck Protection Program).

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Represents the incurred incremental direct origination costs related to the PPP (Paycheck Protection Program).

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Represents the number of new and existing customers related to the PPP (Paycheck Protection Program).

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, before allowance for credit loss and fee, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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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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