Summary of Significant Accounting Policies (tables)

12 Months Ended

Dec. 31, 2011

Accounting Policies Abstract

Schedule Of Regulatory Assets Text Block

			Regulatory Assets
Thousands			2011		2010
Current:
	Unrealized loss on derivatives(1)	$	57,317	$	38,437
	Pension and other postretirement benefit liabilities(2)		15,491		10,988
	Other(3)		21,865		3,289
Total current		$	94,673	$	52,714
Non-current:
	Unrealized loss on derivatives(1)	$	6,536	$	17,022
	Income tax asset		65,264		72,341
	Pension and other postretirement benefit liabilities(2)		170,512		118,248
	Environmental costs(4)		105,670		114,311
	Other(3)		23,410		26,975
Total non-current		$	371,392	$	348,897

Schedule Of Regulatory Liabilities Text Block

			Regulatory Liabilities
Thousands			2011		2010
Current:
	Gas costs	$	17,994	$	15,583
	Unrealized gain on derivatives(1)		2,853		2,245
	Other(3)		10,199		-
Total current		$	31,046	$	17,828
Non-current:
	Gas costs	$	8,420	$	2,297
	Unrealized gain on derivatives(1)		-		628
	Accrued asset removal costs		267,355		252,941
	Other(3)		2,607		2,165
Total non-current		$	278,382	$	258,031