DEBT - Prior Debt Facilities and First and Second Lien Notes (Details) - USD ($)			12 Months Ended
	Jun. 29, 2017	Mar. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 06, 2017	Feb. 11, 2014	Jul. 31, 2013
Debt Instrument [Line Items]
Proceeds from equity offering			$ 0	$ 20,777,000	$ 83,267,000
Interest capitalized to debt principal			$ 7,787,000	0	$ 0
Private Placement | Common Stock
Debt Instrument [Line Items]
Proceeds from equity offering	$ 15,900,000	$ 5,100,000
Associated issuance costs	200,000
Revolving Credit Facility | Senior Notes | Revolving Credit Facility
Debt Instrument [Line Items]
Aggregate principal debt amount								$ 75,000,000.0
Term Loan B Facility | Senior Notes
Debt Instrument [Line Items]
Aggregate principal debt amount								250,000,000.0
Delayed Draw Term Loan B Facility | Senior Notes
Debt Instrument [Line Items]
Aggregate principal debt amount								$ 150,000,000.0
Priming Credit Agreement | Credit Facility
Debt Instrument [Line Items]
Aggregate principal debt amount						$ 25,000,000
First Lien Note Facility | Senior Notes
Debt Instrument [Line Items]
Aggregate principal debt amount	200,000,000
Quarterly installment amortization			0.625%
Early repayment premium base rate			5.00%
Principal prepayment limit			$ 50,000,000
Penalty interest rate increase			2.00%
First Lien Note Facility | Senior Notes | Redemption Period One
Debt Instrument [Line Items]
Early repayment premium			4.00%
First Lien Note Facility | Senior Notes | Redemption Period Two
Debt Instrument [Line Items]
Early repayment premium			2.00%
First Lien Note Facility | Senior Notes | Redemption Period Three
Debt Instrument [Line Items]
Early repayment premium			0.00%
First Lien Note Facility | Senior Notes | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			6.00%
First Lien Note Facility | Senior Notes | Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
First Lien Note Facility | Senior Notes | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			7.00%
First Lien Note Facility | Senior Notes | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
First Lien Note Facility | Senior Notes | Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Second Lien Note Facility | Senior Notes
Debt Instrument [Line Items]
Aggregate principal debt amount	100,000,000
Early repayment premium base rate			5.00%
Penalty interest rate increase			2.00%
Interest capitalized to debt principal			$ 7,800,000	$ 0
Second Lien Note Facility | Senior Notes | Redemption Period One
Debt Instrument [Line Items]
Early repayment premium			4.00%
Second Lien Note Facility | Senior Notes | Redemption Period Two
Debt Instrument [Line Items]
Early repayment premium			2.00%
Second Lien Note Facility | Senior Notes | Redemption Period Three
Debt Instrument [Line Items]
Early repayment premium			0.00%
Second Lien Note Facility | Senior Notes | Option One
Debt Instrument [Line Items]
Basis spread on variable rate			9.25%
Second Lien Note Facility | Senior Notes | Option Two
Debt Instrument [Line Items]
Basis spread on variable rate			11.25%
Second Lien Note Facility | Senior Notes | Option Three
Debt Instrument [Line Items]
Basis spread on variable rate			10.25%
Second Lien Note Facility | Senior Notes | Option Three, Half Cash
Debt Instrument [Line Items]
Basis spread on variable rate			4.625%
Second Lien Note Facility | Senior Notes | Option Three, Half Capitalized Interest
Debt Instrument [Line Items]
Basis spread on variable rate			5.625%
Second Lien Note Facility | Senior Notes | LIBOR | Option One | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate			1.25%
Second Lien Delayed Draw Notes | Senior Notes
Debt Instrument [Line Items]
Delayed draw permitted	$ 10,000,000
2021 Notes Indenture
Debt Instrument [Line Items]
Aggregate principal debt amount							$ 200,000,000.0
Stated interest rate			8.875%				8.875%