Balance Sheet Components

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

NOTE 3. BALANCE SHEET COMPONENTS

Materials and Supplies, Fuel Stock and Stored Natural Gas

Inventories of materials and supplies, fuel stock and stored natural gas are recorded at average cost for our regulated operations and the lower of cost or market for our non-regulated operations and consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31,		December 31,
	2021		2020
Materials and supplies	$	56,368	$	53,258
Fuel stock		4,843		4,658
Stored natural gas		1,949		9,535
Total	$	63,160	$	67,451

Other Current Assets

Other current assets consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31,		December 31,
	2021		2020
Collateral posted for derivative instruments after netting with outstanding derivative liabilities	$	4,810	$	4,336
Prepayments		25,984		24,411
Income taxes receivable		44,371		49,814
Other		7,757		6,324
Total	$	82,922	$	84,885

Net Utility Property

Net utility property consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31,		December 31,
	2021		2020
Utility plant in service	$	6,865,652	$	6,809,797
Construction work in progress		193,685		175,767
Total		7,059,337		6,985,564
Less: Accumulated depreciation and amortization		2,032,234		1,993,952
Total net utility property	$	5,027,103	$	4,991,612

Other Property and Investments-Net and Other Non-Current Assets

Other property and investments-net and other non-current assets consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31,		December 31,
	2021		2020
Operating lease ROU assets	$	71,410	$	71,891
Finance lease ROU assets		46,428		47,338
Non-utility property		18,398		19,508
Equity investments		61,132		59,318
Investment in affiliated trust		11,547		11,547
Notes receivable		14,665		14,454
Deferred compensation assets		9,469		9,174
Assets held for sale (1)		3,363		3,462
Other		27,552		26,947
Total	$	263,964	$	263,639

(1) The Company is in the process of selling certain subsidiary assets associated with Steam Plant Square and Brew Pub.

Other Current Liabilities

Other current liabilities consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31, 2021		December 31, 2020
Accrued taxes other than income taxes	$	56,630	$	45,099
Derivative liabilities		8,644		14,008
Employee paid time off accruals		28,775		26,495
Accrued interest		28,920		17,083
Pensions and other postretirement benefits		10,512		11,987
Other		28,151		35,159
Total other current liabilities	$	161,632	$	149,831

Other Non-Current Liabilities and Deferred Credits

Other non-current liabilities and deferred credits consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31, 2021		December 31, 2020
Operating lease liabilities	$	68,276	$	67,716
Finance lease liabilities		48,044		48,815
Deferred investment tax credits		29,728		29,866
Asset retirement obligations		17,126		17,194
Derivative liabilities		8,959		37,427
Other		14,524		13,981
Total	$	186,657	$	214,999

Regulatory Assets and Liabilities

Regulatory assets and liabilities consisted of the following as of March 31, 2021 and December 31, 2020 (dollars in thousands):

	March 31, 2021				December 31, 2020
	Current		Non-Current		Current		Non-Current
Regulatory Assets
Energy commodity derivatives	$	3,637	$	3,237	$	2,073	$	5,722
Decoupling surcharge		18,150		6,812		7,123		17,123
Pension and other postretirement benefit plans		—		196,153		—		198,746
Interest rate swaps		—		177,824		—		214,851
Deferred income taxes		—		111,537		—		108,517
Settlement with Coeur d'Alene Tribe		—		39,764		—		40,043
AFUDC above FERC allowed rate		—		48,270		—		47,393
Demand side management programs		—		904		—		3,814
Utility plant to be abandoned		—		27,599		—		28,916
COVID-19 deferrals		—		11,759		—		8,166
Other regulatory assets		7,438		82,062		4,477		77,152
Total regulatory assets	$	29,225	$	705,921	$	13,673	$	750,443
Regulatory Liabilities
Income tax related liabilities	$	15,013	$	395,859	$	14,952	$	399,677
Deferred power costs		18,955		13,859		20,299		17,570
Decoupling rebate		1,396		1,604		1,447		1,519
Utility plant retirement costs		—		330,897		—		325,832
Interest rate swaps		—		17,218		—		15,046
COVID-19 deferrals		—		11,628		—		10,949
Other regulatory liabilities		9,703		12,719		9,737		14,227
Total regulatory liabilities	$	45,067	$	783,784	$	46,435	$	784,820