INDEBTEDNESS (Details Textual) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Long-term Debt, Gross	$ 143,750,000
Debt Instrument, Unamortized Discount	31,578,000
Amortization of Financing Costs	211,000
Convertible Senior Notes [Member]
Long-term Debt, Gross		143,800,000
Proceeds from Issuance of Debt		122,600,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		3.00%
Underlying Shares Of Common Stock Convertible Debt		2,068,793
Debt Instrument, Convertible, Conversion Price		$ 69.48
Debt Instrument, Convertible, Threshold Trading Days		20
Debt Instrument Percent Of Conversion Price		130.00%
Per Note Principal		$ 1,000
Debt Instrument, Unamortized Discount		33,600,000
Deferred Offering Costs		5,500,000
Exercise Price Of Bond Hedge		$ 69.48
Underlying Shares Of Common Stock Bond Hedge		2,068,792
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 96.21
Net Adjustments To Additional Paid In Capital Bond Hedge Acquired Warrant Issued Net		15,600,000
Debt Instrument, Interest Rate, Effective Percentage	7.70%
Debt Instrument, Convertible, Threshold Consecutive Trading Days		30 days
Amortization of Financing Costs		4,200,000
Payments of Stock Issuance Costs		$ 1,300,000