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

No definition available.

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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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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.

+ References

No definition available.

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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://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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

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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No definition available.

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ 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

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- Definition

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

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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.

+ References

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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No definition available.

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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.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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Derivative Financial Instruments - Additional Information (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) Contract	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) Contract	Apr. 04, 2013 USD ($)
Mortgage Servicing Rights Hedge [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	$ 297,000,000		$ 349,000,000
Net (negative) positive ineffectiveness on MSR fair value	3,300,000	$ 2,800,000
Designated as Hedging Instrument [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Accumulated net, after tax gain included in accumulated other comprehensive loss	$ 320,000	35,000
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	$ 653,000		$ 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	$ 430,000
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%
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
Aggregate notional amount of credit risk participation agreements	$ 13,500,000		$ 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	6		6
Aggregate notional amount of credit risk participation agreements	$ 37,100,000		$ 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	336,100,000		351,900,000
Termination value of derivatives	24,000		80,000
Collateral Posted	100,000
Derivatives not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	220,100,000		182,100,000
Valuation adjustment	(210,000)		(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	131,900,000		83,000,000
Valuation adjustment	$ 1,700,000		$ 900,000