Long-Term Debt (Detail Textuals 1) - Revolving credit facility - Option 2 - Eurodollar Borrowings	12 Months Ended
Dec. 31, 2017
Line of Credit Facility [Line Items]
Description of reference rate basis	London Interbank Offering Rate ("LIBOR")
Minimum
Line of Credit Facility [Line Items]
Range of margin based on quarterly debt covenant calculation	1.125%
Maximum
Line of Credit Facility [Line Items]
Range of margin based on quarterly debt covenant calculation	2.125%

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration