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)
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-Article 12
-Section 13
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Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 815
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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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No definition available.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Nominal or face amount used to calculate payments on the derivative liability.

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-Publisher FASB
-Name Accounting Standards Codification
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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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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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The number of derivative instruments of a particular group held by the entity.

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- Definition

The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Derivative and Hedging Activities - Additional Information (Details)	12 Months Ended
	Dec. 31, 2017 USD ($) instrument	Dec. 31, 2016 USD ($) instrument	Dec. 31, 2015 USD ($)
Derivative [Line Items]
Gain (loss) on cash flow hedge ineffectiveness	$ 0	$ 0	$ 0
Amounts reclassified from AOCI to Income	127,492
Derivatives Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative liabilities	352,000
Collateral against obligations	$ 250,000
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Number of derivative liability instruments held \| instrument	2
Aggregate notional amount for derivative liability	$ 60,000,000
Interest Rate Products [Member] \| Derivatives Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Number of derivative instruments held \| instrument	50	36
Derivative, notional amount	$ 734,300,000	$ 582,200,000