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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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Nominal or face amount used to calculate payment on derivative.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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Derivative Instruments and Hedging Activities - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) interest_rate_swap	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($) interest_rate_swap
Derivative [Line Items]
Termination value of derivatives in a net liability position	$ 77.0
Derivative collateral posted	75.8
Not Designated as Hedging Instruments
Derivative [Line Items]
Notional amount of interest rate derivatives	985.0		$ 692.3
Cash Flow Hedging
Derivative [Line Items]
Estimated amount to be transferred from OCI to earnings	$ 1.0
Cash Flow Hedging \| Interest Rate Swap
Derivative [Line Items]
Number of interest rate derivatives held \| interest_rate_swap	4		4
Notional amount of interest rate derivatives	$ 60.0		$ 46.0
Cash Flow Hedging \| Interest Rate Swap \| Federal Home Loan Bank Advances
Derivative [Line Items]
Notional amount of interest rate derivatives	10.0	$ 10.0
Cash Flow Hedging \| Interest Rate Swap \| Trust Preferred Debt
Derivative [Line Items]
Notional amount of interest rate derivatives	26.0
Cash Flow Hedging \| Interest Rate Swap \| Brokered Deposit
Derivative [Line Items]
Notional amount of interest rate derivatives	$ 24.0