Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Total spectrum revenue	$ 1,958	$ 1,418
Spectrum revenue \| Ameren Corporation (“Ameren”)
Disaggregation of Revenue [Line Items]
Total spectrum revenue	206	206
Spectrum revenue \| Evergy Services, Inc. (“Evergy”)
Disaggregation of Revenue [Line Items]
Total spectrum revenue	385	385
Spectrum revenue \| Xcel Energy Services Inc. (“Xcel Energy”)
Disaggregation of Revenue [Line Items]
Total spectrum revenue	935	801
Spectrum revenue \| Tampa Electric Company (“TECO”)
Disaggregation of Revenue [Line Items]
Total spectrum revenue	$ 432	$ 26

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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