Amount of amortization expense attributable to debt issuance costs.

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

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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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Weighted average interest rate of debt outstanding.

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

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

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No definition available.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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Represents the maximum percentage allowed of the borrowing base allowed under a credit agreement.

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Represents the percentage of an asset that serves as a part of a borrowing base under a credit agreement.

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The fixed charge coverage ratio as defined in the credit agreement

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Represents the additional 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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No definition available.

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Represent the time period in which the borrowing capacity can be increased.

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The base dollar amount used to determine if a distribution can be made.

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The lookback period used to determine if a distribution can be made.

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The percentage amount outstanding on the credit facility.

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No definition available.

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Reduction in 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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DEBT (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
DEBT (Details) - USD ($) $ in Thousands	Nov. 01, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018
DEBT
Amortization of debt issuance costs		$ 200	$ 200	$ 344	$ 344
Average excess availability, less than 33% of the commitments \| Base Rate Advances
DEBT
Variable interest rate (as a percent)		1.00%		1.00%
Average excess availability, less than 33% of the commitments \| LIBOR
DEBT
Variable interest rate (as a percent)		2.00%		2.00%
Average excess availability, less than 66.67% of the commitments and more than or equal to 33.33% of the commitments \| Base Rate Advances
DEBT
Variable interest rate (as a percent)		0.75%		0.75%
Average excess availability, less than 66.67% of the commitments and more than or equal to 33.33% of the commitments \| LIBOR
DEBT
Variable interest rate (as a percent)		1.75%		1.75%
Average excess availability, more than or equal to 66.67% of the commitments \| Base Rate Advances
DEBT
Variable interest rate (as a percent)		0.50%		0.50%
Average excess availability, more than or equal to 66.67% of the commitments \| LIBOR
DEBT
Variable interest rate (as a percent)		1.50%		1.50%
Average excess availability more than or equal to fifty percent
DEBT
Unused line fee (as a percent)				0.25%
Average excess availability less than fifty percent
DEBT
Unused line fee (as a percent)				0.375%
Eligible unbilled receivables
DEBT
Borrowing base (as a percent)	75.00%
Letter of credit
DEBT
Amount outstanding		$ 0		$ 0			$ 45,000
Revolving line of credit
DEBT
Maximum borrowing capacity	$ 300,000
Revolving line of credit \| Letter of credit
DEBT
Maximum borrowing capacity		256,400		$ 256,400			$ 270,500
Senior secured credit facility
DEBT
Additional borrowing capacity	$ 150,000
Time frame for increasing borrowing capacity				3 years
Percentage of borrowing base allowed	35.00%
Margin (as a percent)	2.00%
Weighted average interest rate (as a percent)							4.256%
Reduction in borrowing capacity		16,400		$ 16,400		$ 20,800	$ 20,800
Unused portion of available borrowing		240,000		240,000
Debt issuance costs		$ 2,300		$ 2,300			$ 2,600
Senior secured credit facility \| Minimum
DEBT
Percentage of borrowing base allowed	30.00%
Variable interest rate (as a percent)		1.50%		1.50%
Senior secured credit facility \| Maximum
DEBT
Variable interest rate (as a percent)		2.00%		2.00%
Senior secured credit facility \| Base Rate Advances \| Minimum
DEBT
Margin (as a percent)	0.50%
Senior secured credit facility \| Base Rate Advances \| Maximum
DEBT
Margin (as a percent)	1.00%
Senior secured credit facility \| LIBOR
DEBT
Margin (as a percent)	1.00%
Senior secured credit facility \| LIBOR \| Minimum
DEBT
Margin (as a percent)	1.50%
Senior secured credit facility \| LIBOR \| Maximum
DEBT
Margin (as a percent)	2.00%
Senior secured credit facility \| Federal Funds Rate
DEBT
Margin (as a percent)	0.50%
Senior secured credit facility \| Eligible billed receivables
DEBT
Borrowing base (as a percent)	85.00%
Senior secured credit facility \| Eligible inventory
DEBT
Borrowing base (as a percent)	70.00%
Senior secured credit facility \| Net recovery percentage
DEBT
Borrowing base (as a percent)	85.00%
Senior secured credit facility \| Criteria for distributions, scenario one
DEBT
Lookback period	30 days
Percentage outstanding	25.00%
Base amount	$ 37,500
Senior secured credit facility \| Criteria for distributions, scenario two
DEBT
Lookback period	30 days
Percentage outstanding	20.00%
Base amount	$ 30,000
Fixed charge coverage ratio	1.00%
Senior secured credit facility \| Coverage Ratio Criteria
DEBT
Lookback period	60 days
Percentage outstanding	10.00%
Base amount	$ 15,000
Fixed charge coverage ratio	1.00%
Senior secured credit facility \| Letter of credit
DEBT
Maximum borrowing capacity	$ 40,000
Senior secured credit facility \| Swingline loan
DEBT
Maximum borrowing capacity	$ 30,000