CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 87,562	$ 47,650
Defined benefit pension plans:
Amortization of prior service cost	33	33
Amortization of net actuarial loss	1,451	253
Regulatory adjustment	(1,100)	(90)
Net defined benefit pension plans	384	196
Foreign currency translation adjustments	(2,819)	97
Total other comprehensive income (loss), net of tax	(2,435)	293
Comprehensive income	85,127	47,943
Comprehensive income (loss) attributable to noncontrolling interests	(175)	1,739
Comprehensive income attributable to Southwest Gas Holdings, Inc.	$ 85,302	$ 46,204