Amount of affordable housing tax credits and other tax benefits recognized.

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Amount of investment in qualified affordable housing projects.

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

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Qualified Affordable Housing (Details) - USD ($)	3 Months Ended			9 Months Ended
Qualified Affordable Housing (Details) - USD ($)	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Sep. 11, 2019
Schedule of Equity Method Investments [Line Items]
Investment in qualified affordable housing projects		$ 8,900,000		$ 8,900,000		$ 4,800,000
Tax credits to offset amortization expense of investments in affordable housing projects		600,000	$ 700,000	1,700,000	$ 2,200,000
New Qualified Affordable Housing Project
Schedule of Equity Method Investments [Line Items]
Investment in qualified affordable housing projects		7,100,000		7,100,000
New qualified affordable housing project commitment							$ 10,200,000
Forecast \| New Qualified Affordable Housing Project
Schedule of Equity Method Investments [Line Items]
Amortization expense of investments in qualified affordable housing projects	$ 0
Tax credits to offset amortization expense of investments in affordable housing projects	$ 0
Noninterest Expense
Schedule of Equity Method Investments [Line Items]
Amortization expense of investments in qualified affordable housing projects		$ 500,000	$ 700,000	$ 2,800,000	$ 2,000,000.0