Derivatives Pre-Tax Losses (Details) - Designated as Hedging Instrument [Member] - Interest Rate Swap [Member] - Cash Flow Hedging [Member] - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) on interest rate cash flow hedges, pre-tax, accumulated other comprehensive income (loss)	$ (347)	$ (1,137)
Gain (loss) on cash flow hedge ineffectiveness, net	0	0
Other Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on cash flow hedge ineffectiveness, net	0	0
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Cash flow hedge gain (loss) reclassified to interest expense, net	$ (223)	$ (298)

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.

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=64837297&loc=SL5624171-113959

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- Definition

The effective portion of loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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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=64837297&loc=SL5624171-113959

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