CONVERTIBLE NOTE (Details)		3 Months Ended		9 Months Ended
	Jun. 16, 2016 USD ($)	Sep. 30, 2016 USD ($) $ / shares		Sep. 30, 2016 USD ($) d $ / shares shares		Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Net Carrying Amount of Liability Component [Abstract]
Debt issuance costs				$ 6,596,000		$ 0
Convertible Note [Member]
Convertible Debt [Abstract]
Original principal amount	$ 210,000,000	$ 210,000,000	[1]	$ 210,000,000	[1]
Interest rate		4.75%		4.75%
Maturity date				Jun. 15, 2020
Redemption price, percentage of principal amount redeemed				100.00%
Threshold percentage of stock price trigger				180.00%
Threshold trading days | d				20
Threshold final trading days | d				3
Threshold consecutive trading days				30 days
Principal amount increments that can be repurchased upon a change in control or termination of trading of common stock				$ 1,000
Principal amount increments that can be converted				$ 1,000
Holding period following issue date before notes can be converted				6 months
Initial conversion rate (in shares) | shares				21.5054
Initial conversion price (in dollars per share) | $ / shares		$ 46.50		$ 46.50
Proceeds from issuance of notes	210,000,000
Liability component of convertible notes	199,100,000
Equity component of convertible notes allocated to additional paid-in capital	$ 10,900,000
Effective interest rate		7.10%		7.10%
Net Carrying Amount of Liability Component [Abstract]
Principal		$ 210,000,000	[1],[2]	$ 210,000,000	[1],[2]		$ 0
Unamortized debt discount (conversion option)		(10,231,000)		(10,231,000)
Total long-term debt, net		199,769,000		199,769,000
Unamortized debt discount (issuance costs)		(5,854,000)		(5,854,000)
Net carrying amount		193,915,000		193,915,000
Debt issuance costs		6,596,000
Additions to deferred financing cost				6,300,000
Adjustments to additional paid-in capital for debt issuance costs				$ 300,000
Interest expense		3,400,000
Contractual interest		2,500,000
Amortization of debt issuance costs and debt discount		$ 900,000

[1] See Note 12 for more information regarding the convertible note.

[2] The carrying value of the debt reflects the amounts stated in the above table less a debt discount of $3.4 million on the Credit Agreement and $16.1 million on the convertible debt, which is not reflected in this table.