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)
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-Article 12
-Section 13
-Sentence Column B

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Derivative, Percent of Aggregate Principal Amount Hedged

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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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No definition available.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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- Definition

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

+ References

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Fair value of liability arising from a financial instrument or contract used to mitigate a specified risk (hedge), expected to be settled after one year or beyond the normal operating cycle, if longer.

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- Definition

Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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Long-term Debt, Line of Credit and Derivatives - Derivative Financial Instruments (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 16, 2015 USD ($) contract
Debt Instrument [Line Items]
Percent of aggregate principal amount hedged			50.00%
Unrealized gain (loss) from hedge ineffectiveness	$ 400
Interest rate swap liability	0	$ 26
Swap
Debt Instrument [Line Items]
Derivative, notional amount			$ 67,500
Derivative, number of instruments held (contract) \| contract			5
Other non-current assets
Debt Instrument [Line Items]
Interest rate swap liability	400
Liability \| Fair Value, Inputs, Level 2 \| Fair Value, Measurements, Recurring
Debt Instrument [Line Items]
Derivatives	$ 483	$ 38