COMMITTMENTS AND CONTINGENCIES - Fair Value Supply Agreement (Details) - Supply Commitments - Fair Value, Inputs, Level 3 $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($)
Accrued Expenses And Other Short-term Liabilities | Supply Agreement Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of January 1, 2017	$ 166
Payments	(166)
Transfer from long-term to current portion	0
Balance as of March 31, 2017	0
Accrued Expenses And Other Short-term Liabilities | Above Market Supply Agreement Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of January 1, 2017	0
Payments	0
Transfer from long-term to current portion	1,752
Balance as of March 31, 2017	1,752
Accrued Expenses And Other Short-term Liabilities | Selling, general and administrative | Supply Agreement Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loss from increase in fair value	0
Accrued Expenses And Other Short-term Liabilities | Selling, general and administrative | Above Market Supply Agreement Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loss from increase in fair value	0
Other Long-term Liabilities | Above Market Supply Agreement Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of January 1, 2017	2,648
Payments	(155)
Transfer from long-term to current portion	(1,752)
Balance as of March 31, 2017	800
Other Long-term Liabilities | Selling, general and administrative | Above Market Supply Agreement Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loss from increase in fair value	$ 59