Derivative Financial Instruments (Narrative Disclosures) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Derivatives
Interest rate swaps - assets		$ 4,637,000
Interest rate swaps - liabilities	$ 18,346,000	4,637,000
Interest Rate Swaps, Default	0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	(2,396,000)	$ (20,000)
Ineffective portion of hedges	0
To commercial borrowers, corporation receives fixed rates and pays floating rates
Derivatives
Interest rate swaps - assets	18,300,000
Interest rate swaps - liabilities	$ 64,000
To commercial borrowers, corporation receives fixed rates and pays floating rates \| Minimum
Derivatives
Derivative, maturity date	Mar. 31, 2021
To commercial borrowers, corporation receives fixed rates and pays floating rates \| Maximum
Derivatives
Derivative, maturity date	Oct. 31, 2036
To dealer countparties, corporation pays fixed rates and receives floating rates
Derivatives
Interest rate swaps - assets	$ 64,000
Interest rate swaps - liabilities	18,300,000
Interest rate derivative instruments not designated as hedging instruments at fair value, net	$ (18,300,000)
To dealer countparties, corporation pays fixed rates and receives floating rates \| Minimum
Derivatives
Derivative, maturity date	Mar. 31, 2021
To dealer countparties, corporation pays fixed rates and receives floating rates \| Maximum
Derivatives
Derivative, maturity date	Oct. 31, 2036
Interest rate swaps \| Minimum
Derivatives
Derivative, maturity date	Dec. 31, 2021
Interest rate swaps \| Maximum
Derivatives
Derivative, maturity date	Dec. 31, 2027
Not designated as hedging instrument \| To commercial borrowers, corporation receives fixed rates and pays floating rates
Derivatives
Derivative, Notional Amount	$ 326,900,000
Not designated as hedging instrument \| To dealer countparties, corporation pays fixed rates and receives floating rates
Derivatives
Derivative, Notional Amount	326,900,000
Designated as Hedging Instrument [Member] \| Interest rate swaps
Derivatives
Derivative, Notional Amount	$ 54,000,000

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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-Topic 815
-SubTopic 25
-Section 50
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- Definition

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.

+ References

No definition available.

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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- Definition

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

+ References

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- Definition

Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
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-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

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