Fair Value of Derivative Financial Instruments - Terms and Fair Values of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivatives Fair Value [Line Items]
Notional Amount	$ 328,610	$ 328,610
3.718% Interest Rate Swap Maturing October 8, 2022 [Member] \| Cash Flow Hedging [Member]
Derivatives Fair Value [Line Items]
Derivative, Fixed Interest Rate	3.718%
Derivative Asset, Notional Amount	$ 250,000	250,000
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	3,233	3,733
3.300% Interest Rate Swap Maturing January 30, 2021 [Member] \| Cash Flow Hedging [Member]
Derivatives Fair Value [Line Items]
Derivative Liability, Notional Amount	$ 25,774	25,774
Derivative, Fixed Interest Rate	3.30%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	$ (287)	(300)
3.090% Interest Rate Swap Maturing October 30, 2019 [Member] \| Cash Flow Hedging [Member]
Derivatives Fair Value [Line Items]
Derivative Liability, Notional Amount	$ 25,774	25,774
Derivative, Fixed Interest Rate	3.09%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	$ (154)	(214)
2.750% Interest Rate Swap Maturing September 30, 2017 [Member] \| Cash Flow Hedging [Member]
Derivatives Fair Value [Line Items]
Derivative Liability, Notional Amount	$ 27,062	27,062
Derivative, Fixed Interest Rate	2.75%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	$ (14)	$ (83)

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

Fair value, before effects of master netting arrangements, of a financial asset or other 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 assets not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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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

Fair value, before 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 elected not to be offset.

+ References

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- Definition

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

+ References

Reference 1: 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

Reference 2: 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

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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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