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Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk - Effect of Fair Value (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount of Gain or (Loss) Recognized in Income on Derivative | $ 6 | $ 161
Cash Flow Hedging |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount of Gain or (Loss) Recognized in OCI on Derivative | 1,206 | (504)
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income |  | (211)
Cash Flow Hedging | Interest Income (Expense) |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income | (74) | (211)
Interest Rate Products | Other Income (Expense) |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount of Gain or (Loss) Recognized in Income on Derivative | 6 | 161
Interest Rate Products | Cash Flow Hedging |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount of Gain or (Loss) Recognized in OCI on Derivative | 1,206 | (504)
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income |  | (211)
Interest Rate Products | Cash Flow Hedging | Interest Income (Expense) |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income | $ (74) | $ (211)

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying 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 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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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. + Details
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- Definition The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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- Definition Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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