Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2011

Asset Retirement Obligations (Tables) [Abstract]

Change in Asset Retirement Obligations

(In thousands)		2011		2010
Balance at January 1,	$	19,913	$	16,513
Liabilities incurred		85		439
Accretion expense		1,071		1,093
Liabilities settled		(157)		(98)
Revisions in estimated cash flows(a)		(1,739)		1,966
Balance at December 31,	$	19,173	$	19,913