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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Average fixed interest rate related to the group of interest rate derivatives.

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Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Average variable interest rate related to the group of interest rate derivatives.

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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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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

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Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Derivatives (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2021	Dec. 31, 2019
Other Liabilities [Member] \| Interest rate swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 32,389
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	$ (1,055)
Average variable interest rate	2.75%
Average fixed interest rate	3.36%
Average remaining maturity	10 years
Other Assets [Member] \| Interest rate swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 32,389
Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	$ 1,055
Average variable interest rate	2.75%
Average fixed interest rate	3.36%
Average remaining maturity	10 years
Cash Flow Hedging [Member] \| Interest rate swap hedging rolling short-term funding [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 125,000
Cash Flow Hedging [Member] \| Forward-starting interest rate swap hedging rolling one-month funding [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 50,000		$ 50,000
Average variable interest rate	0.00%		0.00%
Average fixed interest rate	1.74%		1.74%
Average remaining maturity	5 years 11 months		6 years 1 month
Cash Flow Hedging [Member] \| Interest rate swap hedging FHLB advances and subordinated notes [Domain] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 50,000
Cash Flow Hedging [Member] \| Interest rate swap hedging deposit accounts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	110,000
Cash Flow Hedging [Member] \| Interest rate swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	335,000
Collateral posted	28,570		$ 6,570
Cash Flow Hedging [Member] \| Other Liabilities [Member] \| Forward-starting interest rate swap hedging rolling one-month funding [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Interest rate cash flow hedge liability at fair value	(3,600)		(343)
Cash Flow Hedging [Member] \| Other Liabilities [Member] \| Interest rate swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	285,000		215,000
Interest rate cash flow hedge liability at fair value	$ (23,060)		$ (5,786)
Average variable interest rate	1.08%		1.84%
Average fixed interest rate	2.28%		2.26%
Average remaining maturity	5 years 2 months 12 days		5 years 6 months
Cash Flow Hedging [Member] \| Other Assets [Member] \| Interest rate swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount			$ 70,000
Interest rate cash flow hedge asset at fair value			$ 403
Average variable interest rate			2.62%
Average fixed interest rate			2.37%
Average remaining maturity			5 years 2 months 12 days
Forecast [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative instruments, gain (loss) reclassification from AOCI to interest expense, estimated net amount to be transferred		$ 3,437