Fair Value Of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value, Assets And Liabilities Measured On Recurring Basis

The following table summarizes the Company’s financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2016 and December 31, 2015:

			Fair Value Measurement Using
	Total Fair Value		Level 1		Level 2		Level 3
	(In thousands)
As of December 31, 2016:
Assets:
Investments in money market funds	$	134,790	$	134,790	$	—	$	—
Debt securities issued by the U.S. Treasury	1,626,764		1,626,764		—		—
Equity securities of public companies	2,174		2,174		—		—
Foreign currency forward contracts (1)	242		—		242		—
Total	$	1,763,970	$	1,763,728	$	242	$	—
Liabilities:
Contingent interest derivative on Subordinated Convertible Debentures	$	14,339	$	—	$	—	$	14,339
Foreign currency forward contracts (2)	87		—		87		—
Total	$	14,426	$	—	$	87	$	14,339
As of December 31, 2015:
Assets:
Investments in money market funds	$	137,593	$	137,593	$	—	$	—
Debt securities issued by the U.S. Treasury	1,685,882		1,685,882		—		—
Equity securities of public companies	890		890		—		—
Foreign currency forward contracts (1)	230		—		230		—
Total	$	1,824,595	$	1,824,365	$	230	$	—
Liabilities:
Contingent interest derivative on Subordinated Convertible Debentures	$	30,126	$	—	$	—	$	30,126
Foreign currency forward contracts (2)	164		—		164		—
Total	$	30,290	$	—	$	164	$	30,126

(1) Included in Other current assets

(2) Included in Accounts payable and accrued liabilities

Changes In Fair Value Measurement Of Level 3 Items

The following table summarizes the change in the fair value of the Company’s contingent interest derivative on Subordinated Convertible Debentures during the year ended December 31, 2016 and 2015:

	Year Ended December 31,
	2016			2015
	(In thousands)
Beginning balance	$	30,126		$	26,755
Unrealized (gain) loss on contingent interest derivative on Convertible Debentures	(2,402		)	14,130
Payment of contingent interest	(13,385		)	(10,759		)
Ending balance	$	14,339		$	30,126