Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226016-175313

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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.

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No definition available.

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- Definition

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

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

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Derivative Financial Instruments (Narrative Disclosures) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Derivatives
Fair value of interest rate swaps	$ 704,000		$ 704,000		$ 942,000
Interest rate swap contracts not designated as hedging instruments - liabilities, gross	704,000		704,000		$ 942,000
Derivative asset, fair value, amount offset against collateral	0		0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	358,000	$ 0	1,030,000	$ 0
To commercial borrowers, corporation receives fixed rates and pays floating rates
Derivatives
Fair value of interest rate swaps	687,000		687,000
Interest rate swap contracts not designated as hedging instruments - liabilities, gross	704,000		$ 704,000
To commercial borrowers, corporation receives fixed rates and pays floating rates \| Minimum
Derivatives
Derivative, maturity date			Sep. 30, 2018
To commercial borrowers, corporation receives fixed rates and pays floating rates \| Maximum
Derivatives
Derivative, maturity date			Jul. 15, 2034
To dealer countparties, corporation pays fixed rates and receives floating rates
Derivatives
Fair value of interest rate swaps	704,000		$ 704,000
Interest rate swap contracts not designated as hedging instruments - liabilities, gross	687,000		687,000
Interest rate derivative instruments not designated as hedging instruments at fair value, net	17,000		$ 17,000
To dealer countparties, corporation pays fixed rates and receives floating rates \| Minimum
Derivatives
Derivative, maturity date			Sep. 30, 2018
To dealer countparties, corporation pays fixed rates and receives floating rates \| Maximum
Derivatives
Derivative, maturity date			Jul. 15, 2034
Interest rate swaps \| Minimum
Derivatives
Derivative, maturity date			Jun. 27, 2027
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
Notional value of interest rate swaps with various commercial borrowers	93,200,000		$ 93,200,000
Not Designated as Hedging Instrument \| To dealer countparties, corporation pays fixed rates and receives floating rates
Derivatives
Notional value of interest rate swaps with various commercial borrowers	93,200,000		93,200,000
Designated as Hedging Instrument [Member] \| Interest rate swaps
Derivatives
Notional value of interest rate swaps with various commercial borrowers	$ 30,000,000		$ 30,000,000