Utility Plant and Leases (Tables)

12 Months Ended

Dec. 31, 2020

Net utility plant as of December 31, 2020 and 2019 was as follows:


	December 31,
(Thousands of dollars)	2020		2019
Gas plant:
Storage	$	101,203	$	100,908
Transmission	400,657		391,864
Distribution	7,078,656		6,581,043
General	515,879		467,274
Software and software-related intangibles	270,883		256,299
Other	16,722		15,833
	8,384,000		7,813,221
Less: accumulated depreciation and amortization	(2,419,348)		(2,313,050)
Construction work in progress	211,429		185,026
Net utility plant	$	6,176,081	$	5,685,197

Depreciation and amortization expense on gas plant, including intangibles, was as follows:


(Thousands of dollars)	2020		2019		2018
Depreciation and amortization expense	$	215,636	$	197,358	$	185,719

The components of lease expense were as follows:


(Thousands of dollars)	2020		2019
Southwest:
Operating lease cost	$	1,251	$	1,531

Centuri:
Operating lease cost	$	14,294	$	12,235

Finance lease cost:
Amortization of ROU assets	$	140	$	137
Interest on lease liabilities	37		34
Total finance lease cost	177		171
Short-term lease cost	19,806		16,217
Total lease cost - Southwest Gas Holdings, Inc.	$	35,528	$	30,154

Supplemental cash flow information related to leases for the years ended December 31, 2020 and 2019 was as follows:


	2020
(Thousands of dollars)	Southwest		Centuri		Total
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	766	$	12,889	$	13,655
Operating cash flows from finance leases	—		36		36
Financing cash flows from finance leases	—		199		199

ROU assets obtained in exchange for lease obligations:
Operating leases	$	1,547	$	19,372	$	20,919
Finance leases	—		361		361


	2019
(Thousands of dollars)	Southwest		Centuri		Total
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,278	$	11,166	$	12,444
Operating cash flows from finance leases	—		33		33
Financing cash flows from finance leases	—		212		212

ROU assets obtained in exchange for lease obligations:
Operating leases	$	862	$	23,825	$	24,687
Finance leases	—		13,839		13,839

Supplemental information related to leases, including location in the Consolidated Balance Sheets, is as follows:


(Thousands of dollars)	December 31,
	2020			2019
Southwest:
Operating leases:
Net utility plant	$	2,195		$	1,443

Other current liabilities	$	656		$	723
Other deferred credits and other long-term liabilities	1,586			730
Total operating lease liabilities	$	2,242		$	1,453

Weighted average remaining lease term (in years)	4.24			2.88
Weighted average discount rate	4.49		%	3.18		%

Centuri:
Operating leases:
Other property and investments	$	81,010		$	78,954

Other current liabilities	$	10,032		$	8,851
Other deferred credits and other long-term liabilities	75,247			73,323
Total operating lease liabilities	$	85,279		$	82,174

Finance leases:
Other property and investments	$	752		$	14,264

Other current liabilities	$	202		$	13,769
Other deferred credits and other long-term liabilities	490			355
Total finance lease liabilities	$	692		$	14,124

Weighted average remaining lease term (in years)
Operating leases	10.08			10.25
Finance leases	2.12			2.13

Weighted average discount rate
Operating leases	4.05		%	4.03		%
Finance leases	5.55		%	6.10		%

The following are schedules of maturities of lease liabilities as of December 31, 2020:

The following are schedules of maturities of lease liabilities as of December 31, 2020: