Financial Instruments and Fair Value Measurements (Details Textual) - Interest Rate Swap [Member] - Not Designated as Accounting Hedge [Member] $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($) Agreement
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative instrument, number of outstanding agreement \| Agreement	1
Derivative instrument, notional amount	$ 650.0
Derivative instrument, expiration date	Dec. 31, 2020
Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value liability	$ 8.0

Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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- Definition

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

+ 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.

+ References

No definition available.

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