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Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of the fee that accompanies borrowing money under the debt instrument.

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Increase for accrued, but unpaid interest on the debt instrument for the period.

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

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The amount of cash paid for interest during the period.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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DEBT (Details)			3 Months Ended
DEBT (Details)	Aug. 04, 2015 USD ($)	Jun. 30, 2015 USD ($) $ / shares	Mar. 31, 2016 USD ($) day $ / shares	Jun. 30, 2015 USD ($) $ / shares	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Mar. 09, 2015 USD ($)
Debt Instrument [Line Items]
Proceeds from Convertible Debt		$ 436,400,000		$ 600,000,000
Convertible Debt, Noncurrent			$ 429,900,000			$ 424,600,000
Cash paid for interest			$ 7,000		$ 2,317,000
Conversion Option
Debt Instrument [Line Items]
Derivative Liability, Fair Value, Gross Liability		167,000,000		167,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 100,000,000
Percentage to Increase or Decrease Applicable Margin	0.75%
Barclays Senior Credit Facilities
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount		17,800,000		$ 17,800,000
Barclays Senior Credit Facilities \| Revolver
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 50,000,000
Barclays Senior Credit Facilities \| Term Loan
Debt Instrument [Line Items]
Interest Expense, Debt					4,000,000
Accretion Expense					200,000
Long-term debt							$ 435,000,000
Repayments of Long-term Debt		435,000,000
Cash paid for interest		1,400,000			3,800,000
Gains (Losses) on Extinguishment of Debt		$ 16,900,000
Debt Instrument, Fee Amount					$ 2,300,000
Convertible Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.00%	2.00%	2.00%
Conversion of Stock, Conversion Ratio			15.7858	0.0157858
Debt Instrument, Convertible, Conversion Price (in Dollars per share) \| $ / shares		$ 63.35	$ 63.35	$ 63.35
Debt Instrument, Convertible, Threshold Trading Days \| day			20
Debt Instrument, Convertible, Threshold Consecutive Trading Days			30 days
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger			130.00%
Debt Issuance Cost		$ 18,700,000		$ 18,700,000
Interest Expense, Debt			$ 8,300,000
Debt Instrument, Increase, Accrued Interest			3,000,000
Accretion Expense			5,300,000
Interest Payable			$ 3,500,000			$ 500,000
Convertible Debt \| Conversion Circumstance 2
Debt Instrument [Line Items]
Debt Instrument, Convertible, Threshold Trading Days \| day			5
Debt Instrument, Convertible, Threshold Consecutive Trading Days			10 days
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger			98.00%