BUSINESS COMBINATION AND DIVESTITURE OF ASSETS - Purchase Price Allocation (Details) - USD ($) $ in Thousands			12 Months Ended
	Mar. 31, 2015	Mar. 26, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Cash paid upon consummation			$ 33,430	$ 29,150	$ 0
Fair Value of Assets Acquired and Liabilities Assumed
Goodwill			936	$ 936
Manchester Pharmaceuticals LLC
Business Acquisition [Line Items]
Cash paid upon consummation		$ 29,150
Secured promissory note		31,283
Fair value of business combination-related contingent consideration		12,800
Total Purchase Price		73,233
Fair Value of Assets Acquired and Liabilities Assumed
Acquired product rights-Cholbam (Intangible Asset)		72,000
Inventory		517
Prepaid expenses		116
Goodwill		936
Other asset		1,522
Accounts payable and accrued expenses		(286)
Other liability		(1,522)
Total allocation of purchase price consideration		73,233
Manchester Pharmaceuticals LLC | Product rights
Fair Value of Assets Acquired and Liabilities Assumed
Intangible assets		71,372
Manchester Pharmaceuticals LLC | Trade names
Fair Value of Assets Acquired and Liabilities Assumed
Intangible assets		175	200
Manchester Pharmaceuticals LLC | Customer relationships
Fair Value of Assets Acquired and Liabilities Assumed
Intangible assets		$ 403	$ 400
Asklepion Pharmaceuticals LLC
Business Acquisition [Line Items]
Cash paid upon consummation	$ 33,430
Present value of contingent consideration and service fees	42,010
Fair Value of 661,279 shares issued to Asklepion	15,844
Total Purchase Price	91,284
Fair Value of Assets Acquired and Liabilities Assumed
Acquired product rights-Cholbam (Intangible Asset)	83,200
Pediatric Priority Review Voucher	96,250
Inventory	777
Deferred tax liability	(39,880)
Total Allocation of Purchase Price	88,500
Bargain Purchase Gain	(49,063)
Total Purchase Price	91,284
Total allocation of purchase price consideration	$ 140,347