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 amortization expense 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 ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 11, 2019
Schedule of Equity Method Investments [Line Items]
Investments in qualified affordable housing projects		$ 4.8	$ 6.3
Tax credits to offset amortization expense of investments in affordable housing projects		4.2	3.1	$ 3.4
Noninterest Expense
Schedule of Equity Method Investments [Line Items]
Amortization expense of investments in qualified affordable housing projects		2.6	$ 2.7	$ 3.0
New Qualified Affordable Housing Project
Schedule of Equity Method Investments [Line Items]
Investments in qualified affordable housing projects		$ 1.5
New qualified affordable housing project commitments					$ 10.2
New Qualified Affordable Housing Project \| Forecast
Schedule of Equity Method Investments [Line Items]
Tax credits to offset amortization expense of investments in affordable housing projects	$ 0.5