Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Inventories

Inventories

Inventories are stated at average cost. Inventory consisted of the following (in thousands):

	December 31,
	2019		2018
Materials and supplies	$	42,791	$	36,926
Storage gas and fuel	11,134		13,889
Total Inventories	$	53,925	$	50,815

Other Noncurrent Liabilties

Other noncurrent liabilities consisted of the following (in thousands):

	December 31,
	2019		2018
Pension and other employee benefits	$	128,853	$	125,809
Future QF obligation, net	92,937		102,260
Customer advances	56,870		50,089
Asset retirement obligations	42,449		40,659
Environmental	27,741		28,741
Other	38,302		52,264
Total Noncurrent Liabilities	$	387,152	$	399,822

Supplemental Cash Flow Information

Supplemental Cash Flow Information

	Year Ended December 31,
	2019			2018		2017
				(in thousands)
Cash (received) paid for:
Income taxes	$	(6,737	)	$	55	$	60
Interest	83,776			76,499		82,692
Significant non-cash transactions:
Capital expenditures included in trade accounts payable	33,473			21,625		15,848