Long-Term Debt (Tables)

3 Months Ended

Mar. 31, 2015

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments

Long-term debt consists of the following:

	March 31, 2015			December 31, 2014
	(in thousands)
Senior notes:
3.25% Convertible senior notes due 2016:
Principal amount	$	115,000		$	115,000
Unamortized discount	(5,049		)	(6,077		)
3.25% Convertible senior notes due 2016, net of discount	109,951			108,923
7.75% Senior notes due 2022	500,000			500,000
Total senior notes	609,951			608,923
Revolving credit facility	—			56,000
Long-term debt	$	609,951		$	664,923