Supplemental Disclosure of Cash Flow Information - Summary of Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Cash paid during the period:
Taxes paid, including excise tax	$ 5,808	$ 1,728
Operating leases paid	2,029	2,311
Non-cash investing activity:
Capitalized change in estimated asset retirement obligations	55	(107)
Network equipment provided in exchange for wireless licenses	0	190
Narrowband spectrum licenses received in connection with the LCRA Agreement	0	1,430
Derecognition of contingent liability related to sale of intangible assets	21,404	0
Rights of use asset for new leases	736	796
Rights of use asset for modifications and renewals	$ (35)	$ 1,258

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