Amount of amortization expense attributable to debt issuance costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 220
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- References

No definition available.

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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- Definition

The effective interest rate at the end of the reporting period.

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- Definition

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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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the required periodic payments of both interest and principal.

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- Definition

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

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the noncurrent portion 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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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Type:	credit
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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
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REVOLVING LOAN (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
REVOLVING LOAN (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 27, 2018	Dec. 31, 2017	May 07, 2014
Loan agreement [Abstract]
Debt instrument outstanding amount	$ 178,000			$ 178,000			$ 0
Capitalized costs net of accumulated amortization	1,330		$ 650	1,330	$ 650
Write off of deferred financing costs		$ 363
Amortization expense pertaining to capitalized costs	$ 70		$ 117	$ 610	$ 360
Credit Agreement [Member]
Loan agreement [Abstract]
Period for senior secured credit agreement				5 years
Maximum borrowing capacity						$ 500,000
Maturity date				Jun. 27, 2023
Interest rate on credit agreement	3.367%			3.367%
Commitment fee percentage				0.175%
Unused portion of revolving loan	$ 322,000			$ 322,000
Credit Agreement [Member] \| Minimum [Member]
Loan agreement [Abstract]
Commitment fee percentage				0.15%
Credit Agreement [Member] \| Maximum [Member]
Loan agreement [Abstract]
Commitment fee percentage				0.275%
Term Loan A [Member]
Loan agreement [Abstract]
Maximum borrowing capacity								$ 350,000
Maturity date				May 31, 2019
Payment for outstanding balance				$ 210,750
Revolving Credit Facility [Member]
Loan agreement [Abstract]
Maximum borrowing capacity								$ 100,000
Installment payments required				$ 0