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GOVERNMENT SUPPORT AND SPECTRUM MATTERS (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($) item	Mar. 31, 2022 USD ($)	Apr. 30, 2023 USD ($)	Jul. 31, 2022 USD ($)	Jul. 15, 2022 USD ($)	Jul. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)
Mobility Fund [Line Items]
Revenue from contract with customer	$ 172,557	$ 159,912
Total	185,774	172,019
Communication services
Mobility Fund [Line Items]
Total	181,308	166,543
USF, CAF II, RDOF and Other Programs \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	26,978	16,193
USF, CAF II, RDOF and Other Programs \| US Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	25,577	13,432
USF, CAF II, RDOF and Other Programs \| International Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	$ 1,401	2,761
Universal Service Fund programs
Mobility Fund [Line Items]
Number Of Fund Disbursement Programs \| item	4
High cost support program \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	$ 3,891	3,817
High cost support program \| US Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	2,494	1,056
High cost support program \| International Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	1,397	2,761
CAF II \| Grant receivable through December 2025
Mobility Fund [Line Items]
Amount that has been funded or will be funded	27,700
CAF II \| Grant receivable from January 2026 through July 2028
Mobility Fund [Line Items]
Amount that has been funded or will be funded	8,000
CAF II \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	6,815	6,822
CAF II \| US Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	6,815	6,822
TBCP
Mobility Fund [Line Items]
Grant funds awarded during the period	145,500
Vija's annual USF support
Mobility Fund [Line Items]
Amount that has been funded or will be funded						$ 10,900	$ 16,400
Vija's annual USF support \| Grant Receivable July 2022 Through June 2023
Mobility Fund [Line Items]
Amount that has been funded or will be funded				$ 5,500
Vija's annual USF support \| Subsequent event \| Grant Receivable July 2023 Through December 2025
Mobility Fund [Line Items]
Amount that has been funded or will be funded			$ 5,500
RDOF
Mobility Fund [Line Items]
Grant Funds Expected To Be Awarded	$ 22,700
Grant Fund Term	10 years
Number Of Households To Receive Broadband Coverage \| item	10,000
RDOF \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	$ 608
RDOF \| US Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	608
Other Programs \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	15,664	5,554
Other Programs \| US Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	15,660	$ 5,554
Other Programs \| International Telecom \| Communication services
Mobility Fund [Line Items]
Revenue from contract with customer	4
Remove And Replace Program
Mobility Fund [Line Items]
Receivable for costs expected to be reimbursed	$ 6,700
Remove And Replace Program \| Maximum
Mobility Fund [Line Items]
Amount of cost reimbursement allocated					$ 207,000