Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis

(In thousands)	Level 1		Level 2		Level 3
2017
Assets Carried at Fair Value:
Cash equivalents	$	9,163	$	—	$	—
Liabilities Carried at Fair Value:
Acquired contingent consideration		—		—		113,000
2016
Assets Carried at Fair Value:
Cash equivalents	$	18,514	$	—	$	—
Liabilities Carried at Fair Value:
Acquired contingent consideration		—		—		72,100

Contingent consideration liability

Schedule of Contingent Liabilities

(In thousands)	Year ended December 31,         2017		Year ended December 31,         2016
Acquired contingent consideration:
Balance, beginning of period	$	72,100	$	63,500
Fair value change to contingent consideration (unrealized)    included in the statement of operations		40,900		8,600
Balance, end of period	$	113,000	$	72,100