ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Principles of Consolidation (Details) - USD ($)		1 Months Ended
Apr. 02, 2015	Oct. 31, 2013
Royalties and milestones \| PDL BioPharma
Debt Instrument [Line Items]
Royalty and milestone payments received		$ 240,500,000
Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount of notes issued	$ 575,000,000.0
Proceeds from the issuance of debt	$ 562,000,000

Face (par) amount of debt instrument at time of issuance.

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