Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2016

Asset Retirement Obligation [Abstract]

Reconciliation of the company's asset retirement obligation

A reconciliation of the Company's liability, which is included in other accrued liabilities and deferred credits and other liabilities - other on the Consolidated Balance Sheets, for the years ended December 31 was as follows:

	2016			2015
	(In thousands)
Balance at beginning of year	$	242,224		$	27,211
Liabilities incurred	15,114			2,751
Liabilities settled	(4,338		)	(1,708		)
Accretion expense	13,918			2,134
Revisions in estimates	48,052			211,836
Balance at end of year	$	314,970		$	242,224