Derivative Financial Instruments - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($) interest_rate_swap	Dec. 31, 2020 USD ($) interest_rate_swap
Derivative [Line Items]
Termination value of derivatives in a net liability position	$ 41.7
Derivative collateral posted	58.8
Designated as Hedges
Derivative [Line Items]
Estimated amount to be transferred from accumulated other comprehensive income to earnings	1.0
Non-designated Hedges
Derivative [Line Items]
Notional amount of interest rate derivatives	$ 1,000.0	$ 985.0
Cash Flow Hedging \| Interest rate swap \| Designated as Hedges
Derivative [Line Items]
Number of interest rate derivatives held \| interest_rate_swap	4	4
Notional amount of interest rate derivatives	$ 60.0	$ 60.0
Cash Flow Hedging \| Interest rate swap \| Trust Preferred Debt \| Designated as Hedges
Derivative [Line Items]
Notional amount of interest rate derivatives	26.0
Cash Flow Hedging \| Interest rate swap \| Federal Home Loan Bank advances \| Designated as Hedges
Derivative [Line Items]
Notional amount of interest rate derivatives	10.0
Cash Flow Hedging \| Interest rate swap \| Brokered Deposit \| Designated as Hedges
Derivative [Line Items]
Notional amount of interest rate derivatives	$ 24.0

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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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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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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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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