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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- Definition

The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

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- Definition

Amount of net positive or negative ineffectiveness from comparing the total hedge cost to the changes in fair value of Mortgage Servicing Rights derivative assets attributable to interest rate changes.

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No definition available.

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- Definition

The number of risk participation agreements the entity has entered into.

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- Definition

Termination value of derivatives in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to a provision from agreements with each of its derivative counterparties stating that the entity will be considered on default on its derivative obligations if the entity defaulted on payment of indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender.

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- Definition

Amount of positive (negative) valuation adjustment on the fair value of derivative instruments, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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- Definition

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.

+ References

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

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

Fixed interest rate related to the interest rate derivative.

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No definition available.

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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

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- Definition

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

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The face amount of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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No definition available.

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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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- 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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount before tax 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).

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Derivative Financial Instruments - Additional Information (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) Contract	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Contract	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) Contract	Apr. 04, 2013 USD ($)
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Accumulated net, after tax gain included in accumulated other comprehensive loss	$ 52,000	$ 53,000	$ 611,000	$ (99,000)
Mortgage Servicing Rights Hedge [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	252,000,000		252,000,000		$ 349,000,000
Net (negative) positive ineffectiveness on MSR fair value	72,000	$ (2,600,000)	$ 3,500,000	1,000,000
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Period for which cash flow hedges will be used to hedge quarterly interest payments			5 years
Derivative inception date			Dec. 31, 2014
Derivative maturity date			Dec. 31, 2019
Description of variable rate basis for derivative			three-month LIBOR
Ineffectiveness related to interest rate swap designated as a cash flow hedge			$ 0	$ 0
Accumulated net, after tax gain included in accumulated other comprehensive loss			$ 639,000		$ 278,000
The period over which OCI will be reclassified as interest expense			12 months
Estimated amount to be reclassified as a decrease to interest expense	$ 644,000		$ 644,000
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Junior Subordinated Debentures [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount						$ 60,000,000
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Three-month LIBOR [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Swap fixed interest rate to be paid	1.66%		1.66%
Derivatives not Designated as Hedging Instruments [Member] \| Beneficiary [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of risk participation agreements \| Contract	2		2		2
Aggregate notional amount of credit risk participation agreements	$ 13,200,000		$ 13,200,000		$ 13,700,000
Derivatives not Designated as Hedging Instruments [Member] \| Guarantor [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of risk participation agreements \| Contract	7		7		6
Aggregate notional amount of credit risk participation agreements	$ 40,300,000		$ 40,300,000		$ 37,100,000
Derivatives not Designated as Hedging Instruments [Member] \| Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	410,200,000		410,200,000		351,900,000
Termination value of derivatives	0		0		80,000
Collateral Posted	0		0
Derivatives not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	199,500,000		199,500,000		182,100,000
Valuation adjustment			930,000		(237,000)
Derivatives not Designated as Hedging Instruments [Member] \| Interest Rate Lock Commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	$ 102,900,000		102,900,000		83,000,000
Valuation adjustment			$ 893,000		$ 900,000