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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959

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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.

+ References

No definition available.

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

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Derivative Financial Instruments (Back-to-back loan swaps) (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Derivative [Line Items]
Cash pledged as collateral	$ 0		$ 1,200,000
Counterparties
Derivative [Line Items]
Cash pledged as collateral	860,000		0
Back-to-Back Loan Swaps \| Interest Rate Swap
Derivative [Line Items]
Cash pledged as collateral	495,000		1,600,000
Back-to-Back Loan Swaps \| Interest Rate Swap \| Interest income
Derivative [Line Items]
Gain (loss) recognized	0	$ 0
Back-to-Back Loan Swaps \| Interest Rate Swap \| Counterparties
Derivative [Line Items]
Cash pledged as collateral	$ 1,600,000		$ 190,000