Supplemental Cash Flow Information

12 Months Ended

Dec. 31, 2017

Supplemental Cash Flow Information [Abstract]

Cash Flow, Supplemental Disclosure

Note 12. Supplemental Cash Flow Information

Supplemental Cash Flow Information

	Year Ended December 31,
In thousands	2017			2016			2015
Supplemental cash flow information
Cash paid for interest, expensed	$	98,261		$	130,843		$	146,560
Cash paid for interest, capitalized	30,762			25,982			32,146
Cash paid for interest, treated as a reduction of debt	50,349			25,835			—
Cash paid for income taxes	450			375			6,340
Cash received from income tax refunds	(13,323		)	(2,455		)	(50,163		)
Noncash investing and financing activities
Increase in asset retirement obligations	9,565			11,621			14,866
Increase (decrease) in liabilities for capital expenditures	3,930			(13,593		)	(97,278		)
Retirement of treasury stock	46,562			—			884,129