v3.22.2.2
Document and Entity Information
Sep. 26, 2022
Document And Entity Information [Line Items]  
Amendment Flag false
Entity Central Index Key 0001692115
Document Type 8-K
Document Period End Date Sep. 26, 2022
Entity Registrant Name SOUTHWEST GAS HOLDINGS, INC.
Entity Incorporation State Country Code DE
Entity File Number 001-37976
Entity Tax Identification Number 81-3881866
Entity Address, Address Line One 8360 S. Durango Dr.
Entity Address, Address Line Two Post Office Box 98510
Entity Address, City or Town Las Vegas
Entity Address, State or Province NV
Entity Address, Postal Zip Code 89193-8510
City Area Code (702)
Local Phone Number 876-7237
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Common Stock [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Southwest Gas Holdings, Inc. Common Stock, $1 par value
Trading Symbol SWX
Security Exchange Name NYSE
Preferred Stock Purchase Rights [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Preferred Stock Purchase Rights
Security Exchange Name NYSE