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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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 470
-SubTopic 20
-Section 50
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Amount of the required periodic payments applied to principal.

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

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No definition available.

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Fixed interest rate related to the interest rate derivative.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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).

+ References

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The effective interest rate during the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The cash outflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Debt and Financial Instruments (Details Textual) - USD ($)	1 Months Ended	9 Months Ended
	Apr. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Mar. 01, 2017	Sep. 02, 2014
Short-term Debt [Line Items]
Borrowing capacity						$ 100,000,000
Long-term debt, gross						$ 40,000,000
Debt instrument, periodic payment, principal		$ 1,000,000
Weighted average interest rate		3.80%
Derivative, notional amount	$ 20,000,000				$ 37,000,000
Derivative, fixed Interest Rate					1.59%
Derivative assets (liabilities), at fair value, net		$ 200,000		$ 100,000
Premium paid for interest rate cap	$ (500,000)	$ 0	$ (474,000)
Maximum
Short-term Debt [Line Items]
Line of credit facility, interest rate description		LIBOR market index rate (for borrowings in Dollars and Sterling) or the daily one month EURIBOR (for borrowings in Euros) plus 2.50%
Minimum
Short-term Debt [Line Items]
Line of credit facility, interest rate description		LIBOR market index rate plus 1.25%
LIBOR
Short-term Debt [Line Items]
Derivative, cap interest rate	2.00%
Financing and Security Agreement
Short-term Debt [Line Items]
Borrowing outstanding		$ 69,000,000
Available borrowings		$ 26,300,000
Financing and Security Agreement \| LIBOR \| Maximum
Short-term Debt [Line Items]
Interest rate spread		2.50%
Financing and Security Agreement \| LIBOR \| Minimum
Short-term Debt [Line Items]
Interest rate spread		1.25%
Fourth Amended and Restated Financing and Security Agreement \| Term Loan
Short-term Debt [Line Items]
Long-term Debt		$ 37,000,000
Interest Rate Cap
Short-term Debt [Line Items]
Derivative assets (liabilities), at fair value, net		$ 600,000		$ 300,000