FAIR VALUE MEASUREMENTS (Tables)

6 Months Ended

Jun. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value of Financial Assets and Liabilities

The Company measures certain financial assets and liabilities at fair value on a recurring basis. In addition to available-for-sale debt securities, debt and foreign currency derivatives, which are disclosed in Notes 6, 10 and 11, respectively, the following tables below present the classification within fair value hierarchy of financial assets and liabilities not disclosed elsewhere.

	Fair Value Measurements at June 30, 2018
	Quoted Price in Active Markets For Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets:
Other current assets:
NQDC Plan assets	$	—	$	1,018	$	—	$	1,018
Restricted investments (1)		—		7,721		—		7,721
Total other current assets		—		8,739		—		8,739
Other assets:
NQDC Plan assets		—		12,832		—		12,832
Restricted investments (1)		—		6,889		—		6,889
Strategic investments (2)		1,616		—		—		1,616
Total other assets		1,616		19,721		—		21,337
Total assets	$	1,616	$	28,460	$	—	$	30,076
Liabilities:
Current liabilities:
NQDC Plan liability	$	1,050	$	1,018	$	—	$	2,068
Contingent acquisition consideration		—		—		76,466		76,466
Total current liabilities		1,050		1,018		76,466		78,534
Other long-term liabilities:
NQDC Plan liability	$	18,588	$	12,832		—		31,420
Contingent acquisition consideration		—		—		57,674		57,674
Total other long-term liabilities		18,588		12,832		57,674		89,094
Total liabilities	$	19,638	$	13,850	$	134,140	$	167,628

	Fair Value Measurements at December 31, 2017
	Quoted Price in Active Markets For Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets:
Other current assets:
NQDC Plan assets	$	—	$	967	$	—	$	967
Restricted investments (1)		—		15,647		—		15,647
Total other current assets		—		16,614		—		16,614
Other assets:
NQDC Plan assets	—			11,859		—		11,859
Total other assets		—		11,859		—		11,859
Total assets	$	—	$	28,473	$	—	$	28,473
Liabilities:
Current liabilities:
NQDC Plan liability	$	1,356	$	967	$	—	$	2,323
Contingent acquisition consideration	—		—			53,648		53,648
Total current liabilities		1,356		967		53,648		55,971
Other long-term liabilities:
NQDC Plan liability		18,272		11,859	—			30,131
Contingent acquisition consideration	—		—			135,318		135,318
Total other long-term liabilities		18,272		11,859		135,318		165,449
Total liabilities	$	19,628	$	12,826	$	188,966	$	221,420

(1)   The restricted investments at June 30, 2018 and December 31, 2017 secure the Company’s irrevocable standby letters of credit obtained in connection with certain commercial agreements.

(2) The Company has investments in marketable equity securities measured using quoted prices in an active market that are considered strategic investments and included in other assets on the Company’s Consolidated Balance Sheets.  

Liabilities Measured at Fair Value Using Level 3 Inputs

Contingent acquisition consideration at December 31, 2017	$	188,966
Changes in the fair value of other contingent acquisition consideration		8,284
Milestone payments to Ares Trading S.A. (Merck Serono)		(61,607	)
Foreign exchange remeasurement of Euro denominated contingent    acquisition consideration		(1,503	)
Contingent acquisition consideration at June 30, 2018	$	134,140