Revenue - Disaggregation of Revenue (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($) county	Dec. 31, 2021 USD ($)
Disaggregation of Revenue [Line Items]
Spectrum revenues	$ 578	$ 385	$ 1,311	$ 749
Broadband licenses granted, number of counties | county			70
Spectrum revenue | Ameren
Disaggregation of Revenue [Line Items]
Spectrum revenues	152	202	$ 457	202
Spectrum revenue | Evergy
Disaggregation of Revenue [Line Items]
Spectrum revenues	244	0	308	0
Spectrum revenue | Motorola
Disaggregation of Revenue [Line Items]
Spectrum revenues	$ 182	$ 183	$ 546	$ 547