Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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DEBT - Interest Expense (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
DEBT - Interest Expense (Details) - USD ($) $ in Thousands	Apr. 03, 2018	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Oct. 03, 2017
Debt Instrument [Line Items]
Credit facility interest rate (percentage)													12.00%
Interest expense		$ 299	$ 9,499	$ 9,323	$ 13,409	$ 9,728	$ 9,152	$ 14,541	$ 9,936	$ 32,530	$ 43,357	$ 13,356
Twelve Point Zero Percentage Credit Facility
Debt Instrument [Line Items]
Interest expense										7,513	11,954	3,597
Three Point Zero Percentage Paid In Kind Interest Credit Facility
Debt Instrument [Line Items]
Interest expense										1,886	2,966	900
Accretion Expense Funded Debt
Debt Instrument [Line Items]
Interest expense										11,670	23,632	8,371
Applicable Premium For Principal Prepayment
Debt Instrument [Line Items]
Interest expense	$ 3,100
Accretion Expense for GP Sponsor Note Payable
Debt Instrument [Line Items]
Interest expense										905	68	0
Other Borrowings
Debt Instrument [Line Items]
Interest expense										146	130	488
Principal Prepayments \| Applicable Premium For Principal Prepayment
Debt Instrument [Line Items]
Interest expense										3,103	4,607	0
Principal Payments \| Applicable Premium For Principal Prepayment
Debt Instrument [Line Items]
Interest expense										$ 7,307	$ 0	$ 0
Payment in Kind (PIK) Note
Debt Instrument [Line Items]
Credit facility interest rate (percentage)													3.00%