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 ($)	3 Months Ended		12 Months Ended
Qualified Affordable Housing (Details) - USD ($)	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Sep. 11, 2019
Schedule of Equity Method Investments [Line Items]
Investment in qualified affordable housing projects	$ 6,400,000			$ 4,800,000
Tax credits to offset amortization expense of investments in affordable housing projects	600,000	$ 700,000
New Qualified Affordable Housing Project
Schedule of Equity Method Investments [Line Items]
Investment in qualified affordable housing projects	3,600,000
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	$ 600,000	$ 700,000