v3.26.3
Cover
Oct. 20, 2026
Document Information [Line Items]  
Document Type 8-K
Amendment Flag false
Document Period End Date Oct. 20, 2026
Entity Registrant Name Southwest Gas Holdings, Inc.
Entity Central Index Key 0001692115
Entity File Number 001-37976
Entity Incorporation, State or Country Code DE
Entity Tax Identification Number 81-3881866
Entity Address, Address Line One 8360 S. Durango Dr.
Entity Address, City or Town Las Vegas
Entity Address, State or Province NV
Entity Address, Postal Zip Code 89113
City Area Code 702
Local Phone Number 876-7237
Title of 12(b) Security Southwest Gas Holdings, Inc. Common Stock, $1 Par Value
Trading Symbol SWX
Security Exchange Name NYSE
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Southwest Gas Corporation [Member]  
Document Information [Line Items]  
Amendment Flag false
Entity Registrant Name Southwest Gas Corporation
Entity Central Index Key 0000092416
Entity File Number 001-7850
Entity Incorporation, State or Country Code CA
Entity Tax Identification Number 88-0085720
Entity Address, Address Line One 8360 S. Durango Dr.
Entity Address, City or Town Las Vegas
Entity Address, State or Province NV
Entity Address, Postal Zip Code 89113
City Area Code 702
Local Phone Number 876-7237