LONG TERM DEBT AND CREDIT AGREEMENT (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
	Feb. 26, 2016	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jun. 15, 2015
Credit Facilities [Line Items]
Interest Expense			$ 6,346	$ 1,771	$ 1,574
Increase (Decrease) in Deferred Income Taxes			6,693	(69)	(730)
Capped Call Transaction Costs			(10,125)	0	0
Long-term debt			95,950	0
Repayments of Lines of Credit			65,500	$ 25,500	$ 0
Convertible Debt [Member]
Credit Facilities [Line Items]
Convertible Notes Payable, Noncurrent			$ 125,000			$ 125,000
Net Proceeds from Issuance of Convertible Notes Payable						120,300
Debt Instrument, Convertible, Terms of Conversion Feature			The Notes are convertible into cash, shares of the Company’s common stock or a combination of cash and shares of common stock, at the Company’s election, based on an initial conversion rate, subject to adjustment, of 45.5840 shares per $1,000 principal amount of Notes, which is equal to an initial conversion price of $21.94 per share. Prior to December 15, 2019, the Notes are convertible only in the following circumstances: (1) during any calendar quarter commencing after September 30, 2015, if the last reported sale price of the Company’s common stock is greater than or equal to 130% of the applicable conversion price for at least 20 trading days during a period of 30 consecutive trading days ending on the last trading day of the preceding calendar quarter; (2) during the five business day period after any five consecutive trading day period (the “Measurement Period”) in which the trading price per $1,000 principal amount of Notes for each trading day in the Measurement Period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on such trading day; or (3) upon the occurrence of specified corporate transactions.
Convertible Debt, Noncurrent			$ 95,950			$ 96,700
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Subsequent Adjustments		$ 28,300
Debt Instrument, Interest Rate, Effective Percentage						7.66%
Accretion of Discount			2,900
Interest Expense			4,300
Increase (Decrease) in Deferred Income Taxes		$ 6,500
Convertible Notes Payable Transaction Costs			$ (3,641)
Convertible Debt [Member] | Capped call [Member]
Credit Facilities [Line Items]
Debt Instrument, Call Feature			The Capped Call has a strike price of $21.94 and a cap price of $26.00 and is exercisable by the Company when and if the Notes are converted.
Capped Call Transaction Costs			$ 10,100
Line of credit [Member] | KeyBank National Association [Member]
Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 35,000
Subsequent Event [Member] | Cerberus Business Finance [Member]
Credit Facilities [Line Items]
Credit facilities, interest rate description	Interest accrues on outstanding borrowings under the Credit Facility and the Term Loan at a rate of either the LIBOR Rate (as defined in the Financing Agreement) plus 6.75% or a Reference Rate (as defined in the Financing Agreement) plus 5.75%, at the option of the Company. The Company must also pay to the Lenders, on a monthly basis, an unused line fee at a rate of 0.5% per annum.
Line of Credit Facility, Frequency of Payments	The Company may prepay all or any portion of the Term Loan prior to its stated maturity, subject to the payment of certain fees based on the amount repaid. The Term Loan requires quarterly principal payments of $1.25 million commencing in June 2016. The Term Loan also requires the Company to use excess cash, as defined in the Financing Agreement, to repay outstanding principal
Debt Instrument, Covenant Description	The Financing Agreement contains customary representations and warranties, covenants, mandatory prepayments, and events of default under which the Company’s payment obligations may be accelerated.  The Financing Agreement includes covenants requiring the Company to maintain a Leverage Ratio (defined as the ratio of (a) consolidated total funded indebtedness to (b) consolidated Adjusted EBITDA) of no greater than 4.35:1.00 for the four quarters ending June 30, 2016, 5.40:1.00 for the four quarters ending September 30, 2016, 4.20:1.00 for the four quarters ending December 31, 2016 and thereafter declining over time from 3.50:1.00 to 2.50:1.00.  The Financing Agreement also restricts the Company from making capital expenditures in excess of $20,000,000 in any fiscal year.
Line of Credit Facility, Collateral	The Company granted a security interest on substantially all of their assets to secure the obligations under the Credit Facility and the Term Loan.
Debt Instrument, Restrictive Covenants	The Financing Agreement contains restrictive covenants that are customary for an agreement of this kind, including, for example, covenants that restrict the Company from incurring additional indebtedness, granting liens, making investments and restricted payments, making acquisitions, paying dividends and engaging in transactions with affiliates.
Subsequent Event [Member] | Long-term debt [Member] | Cerberus Business Finance [Member]
Credit Facilities [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 100,000
Long-term debt	100,000
Subsequent Event [Member] | Line of credit [Member] | Cerberus Business Finance [Member]
Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 5,000
Convertible Debt [Member]
Credit Facilities [Line Items]
Convertible Notes Payable Transaction Costs						$ 4,700
Convertible Debt [Member] | Interest Expense [Member]
Credit Facilities [Line Items]
Convertible Notes Payable Transaction Costs						3,600
Convertible Debt [Member] | Equity [Member]
Credit Facilities [Line Items]
Convertible Notes Payable Transaction Costs						$ 1,100