Derivative Financial Instruments (Narrative Disclosures) (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Derivatives
Accumulated Derivative Credit Valuation Adjustment	$ 191,000	$ 461,000
Interest Rate Swaps, Default	0
Unrealized losses on interest rate swaps arising during the period	3,610,000	$ (3,011,000)
Ineffective portion of hedges	0
To commercial borrowers, corporation receives fixed rates and pays floating rates
Derivatives
Interest rate swaps - assets	26,300,000
Interest rate swaps - liabilities	6,600,000
To dealer countparties, corporation pays fixed rates and receives floating rates
Derivatives
Interest rate swaps - assets	6,600,000
Interest rate swaps - liabilities	26,300,000
Interest rate derivative instruments not designated as hedging instruments at fair value, net	(19,700,000)
Not designated as hedging instrument \| To commercial borrowers, corporation receives fixed rates and pays floating rates
Derivatives
Derivative, Notional Amount	640,600,000
Not designated as hedging instrument \| To dealer countparties, corporation pays fixed rates and receives floating rates
Derivatives
Derivative, Notional Amount	640,600,000
Designated as Hedging Instrument \| Interest rate swaps
Derivatives
Derivative, Notional Amount	$ 106,000,000

Accumulated Derivative Credit Valuation Adjustment

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- Definition

Fair value of interest rate swaps that are in default

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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 derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivatives 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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- Definition

Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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