Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2016

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis

Financial assets and liabilities measured at fair value on a recurring basis at March 31, 2016, and December 31, 2015, consisted of the following:

(In thousands)	Fair Value Measurements
At March 31, 2016	Total		Level 1		Level 2		Level 3
Money market fund	$	91,721	$	91,721	$	—	$	—
Mutual funds	$	911	$	911	$	—	$	—
Investments
Federal agency notes	$	248,164	$	—	$	248,164	$	—
Commercial paper	$	32,494	$	—	$	32,494	$	—

(In thousands)	Fair Value Measurements
At December 31, 2015	Total		Level 1		Level 2		Level 3
Money market fund	$	54,761	$	54,761	$	—	$	—
Mutual funds	$	743	$	743	$	—	$	—
Investments
Federal agency notes	$	284,757	$	—	$	284,757	$	—
Commercial paper	$	31,672	$	—	$	31,672	$	—

Financial Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis

Assets and liabilities measured at fair value on a nonrecurring basis at March 31, 2016, and December 31, 2015, consisted of the following:

(In thousands)	Fair Value Measurements
At March 31, 2016	Total		Level 1		Level 2		Level 3
1.875% Convertible debentures	$	524	$	—	$	524	$	—
1.75% Convertible debentures	$	301,127	$	—	$	301,127	$	—

(In thousands)	Fair Value Measurements
At December 31, 2015	Total		Level 1		Level 2		Level 3
1.875% Convertible Debentures	$	524	$	—	$	524	$	—
1.75% Convertible Debentures	$	285,446	$	—	$	285,446	$	—
Long-term investments	$	524	$	524	$	—	$	—