Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2014

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

	Year Ended December 31,
	2014			2013			2012
	(in thousands)
Net cash provided from operating activities included:
Income taxes (refunded from) paid to taxing authorities	$	(156	)	$	(347	)	$	386
Interest paid		165,530			159,137			153,249
Non-cash investing and financing activities included:
Asset retirement costs capitalized, net	$	56,822		$	76,373		$	57,982
Increase (decrease) in accrued capital expenditures		150,604			27,079			(94,121	)