Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Mar. 31, 2025
Amortization related to intangible assets
Finite-lived intangible assets, gross	$ 1,191,898	$ 1,191,681
Accumulated Amortization	(367,383)	(340,334)
Total	$ 824,515	851,347
Customer relationships
Amortization related to intangible assets
Weighted-average remaining amortization period for intangible assets	17 years 7 months 6 days
Finite-lived intangible assets, gross	$ 857,903	857,903
Accumulated Amortization	(284,776)	(264,675)
Total	$ 573,127	593,228
Customer contracts
Amortization related to intangible assets
Weighted-average remaining amortization period for intangible assets	18 years 9 months 18 days
Finite-lived intangible assets, gross	$ 192,000	192,000
Accumulated Amortization	(48,000)	(44,160)
Total	$ 144,000	147,840
Right-of-way and easements
Amortization related to intangible assets
Weighted-average remaining amortization period for intangible assets	28 years 2 months 12 days
Finite-lived intangible assets, gross	$ 100,167	99,964
Accumulated Amortization	(23,441)	(21,645)
Total	$ 76,726	78,319
Debt issuance costs
Amortization related to intangible assets
Weighted-average remaining amortization period for intangible assets	3 years 4 months 24 days
Finite-lived intangible assets, gross	$ 22,323	21,841
Accumulated Amortization	(7,029)	(4,748)
Total	$ 15,294	17,093
Executory contracts and other agreements
Amortization related to intangible assets
Weighted-average remaining amortization period for intangible assets	23 years
Finite-lived intangible assets, gross	$ 19,505	19,973
Accumulated Amortization	(4,137)	(5,106)
Total	$ 15,368	$ 14,867