Selected Balance Sheet Information:

9 Months Ended

Sep. 30, 2021

Selected Balance Sheet Information [Abstract]

Accounts Receivable and Allowance for Credit Losses

Following is a summary of Accounts receivable, net included in the accompanying Condensed Consolidated Balance Sheets (in thousands) as of:


	September 30, 2021		December 31, 2020
Accounts receivable, trade	$	120,930	$	146,899
Unbilled revenue	63,338		126,065
Less: Allowance for credit losses	(2,312)		(7,003)
Accounts receivable, net	$	181,956	$	265,961

Changes to allowance for credit losses for the nine months ended September 30, 2021 and 2020, respectively, were as follows (in thousands):


	Balance at Beginning of Year		Additions Charged to Costs and Expenses		Recoveries and Other Additions		Write-offs and Other Deductions		Balance at September 30,
2021	$	7,003	$	1,111	$	2,420	$	(8,222)	$	2,312
2020	$	2,444	$	8,471	$	3,720	$	(6,026)	$	8,609

Materials, Supplies and Fuel

The following amounts by major classification are included in Materials, supplies and fuel on the accompanying Condensed Consolidated Balance Sheets (in thousands) as of:


	September 30, 2021		December 31, 2020
Materials and supplies	$	85,612	$	85,250
Fuel - Electric Utilities	1,240		1,531
Natural gas in storage	58,891		30,619
Total materials, supplies and fuel	$	145,743	$	117,400

Accrued Liabilities

The following amounts by major classification are included in Accrued liabilities on the accompanying Condensed Consolidated Balance Sheets (in thousands) as of:


	September 30, 2021		December 31, 2020
Accrued employee compensation, benefits and withholdings	$	72,328	$	77,806
Accrued property taxes	44,231		47,105
Customer deposits and prepayments	53,652		52,185
Accrued interest	46,532		31,520
Other (none of which is individually significant)	33,092		34,996
Total accrued liabilities	$	249,835	$	243,612