Long-Term Debt LONG-TERM DEBT (Tables)

12 Months Ended

Dec. 31, 2019

Long-term Debt, Unclassified [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

Long-term debt consisted of the following as of:

	As of December 31,
	2019			2018
	(in thousands)
Senior Notes:
1.125% Convertible Notes due September 2021:
Principal amount	$	200,000		$	200,000
Unamortized discount	(14,763		)	(22,766		)
Unamortized debt issuance costs	(1,666		)	(2,640		)
Net of unamortized discount and debt issuance costs	183,571			174,594
6.125% Senior Notes due September 2024:
Principal amount	400,000			400,000
Unamortized debt issuance costs	(4,611		)	(5,590		)
Net of unamortized debt issuance costs	395,389			394,410
5.75% Senior Notes due May 2026:
Principal amount	600,000			600,000
Unamortized debt issuance costs	(5,734		)	(6,628		)
Net of unamortized debt issuance costs	594,266			593,372
Total senior notes	1,173,226			1,162,376
Revolving Credit Facility:
Revolving credit facility due May 2023	4,000			32,500
Total long-term debt, net of unamortized discount and debt issuance costs	$	1,177,226		$	1,194,876