Long-Term Debt And Other Long-Term Liabilities (Tables)

12 Months Ended

Dec. 31, 2017

Long-term debt and other long-term liabilites [Abstract]

Long Term Debt [Table Text Block]

Long-term debt consisted of the following as of December 31:

	2017			2016
	(In thousands)
Credit agreement with average interest rates of 3.4% and 2.8% at December 31, 2017 and 2016, respectively	$	178,000		$	160,800
6.625% senior subordinated notes due 2021	650,000			650,000
Total principal amount	$	828,000		$	810,800
Less: unamortized discount	(2,234		)	(2,804		)
Less: debt issuance costs, net	(5,490		)	(7,079		)
Total long-term debt	$	820,276		$	800,917

Other Long Term Liabilities [Table Text Block]

Other long-term liabilities consisted of the following as of December 31:

	2017		2016
	(In thousands)
ARO liability	$	69,444	$	70,170
Capital lease obligations	15,224		18,918
Workers’ compensation	13,340		15,163
Separation benefit plans	6,524		4,943
Deferred compensation plan	5,390		4,578
Gas balancing liability	3,283		3,789
Other	—		410
	113,205		117,971
Less current portion	13,002		14,907
Total other long-term liabilities	$	100,203	$	103,064

Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block]

Future payments required under the capital leases at December 31, 2017 are as follows:

	Amount
Ending December 31,	(In thousands)
2018	$	6,168
2019	6,168
2020	6,168
2021	3,768
Total future payments	22,272
Less payments related to:
Maintenance	5,874
Interest	1,174
Present value of future minimum payments	$	15,224