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DISPOSITIONS - Narratives (Details) $ in Thousands			1 Months Ended	3 Months Ended	6 Months Ended		12 Months Ended
DISPOSITIONS - Narratives (Details) $ in Thousands	Jun. 02, 2026 USD ($)	Feb. 11, 2026 USD ($) item	Jun. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2027 USD ($)	Dec. 31, 2025 USD ($)
Disposition
Assets held for sale			$ 8,600	$ 8,600	$ 8,600			$ 11,200
Consideration received					267,669
Telecommunications licenses			105,486	105,486	105,486			105,486
Proceeds from sale of spectrum					2,200
Proceeds from sale of assets					1,585	$ 221
International Telecom
Disposition
Proceeds from sale of assets				1,300
Gain (loss) on disposal of fixed asset				1,100
Telecommunication Spectrum Licenses
Disposition
Telecommunications licenses			36,400	36,400	36,400
Proceeds from sale of spectrum			2,200
Expected Price to be received on sale			37,800
Purchase additional licenses			3,200
Forecast \| Telecommunication Spectrum Licenses
Disposition
Gain of license dispositions							$ 4,600
Maximum \| Forecast \| Telecommunication Spectrum Licenses
Disposition
Proceeds from sale of spectrum							$ 41,000
Tower portfolio \| Held-for-sale \| Transaction agreement with EIP holdings
Disposition
Fixed assets			6,600	6,600	6,600
Lease assets			300	300	300
Lease liabilities			300	300	300
Current portion of lease liabilities			200	200	200
Tower portfolio \| Disposal \| Transaction agreement with EIP holdings
Disposition
Number of tower portfolios agreed to sell \| item		214
Maximum cash consideration		$ 297,000
Anticipated closure term of agreement	11 months
Consideration received	$ 267,700
Cash proceeds from disposal	255,669
Deferred contingent consideration	12,000
Transaction costs	8,464			6,300	7,100			$ 1,400
Fixed assets	27,313
Current portion of lease liabilities	$ 1,110
Tower portfolio \| Disposal \| Transaction agreement with EIP holdings \| Minimum
Disposition
Useful life	6 years
Tower portfolio \| Disposal \| Transaction agreement with EIP holdings \| Maximum
Disposition
Useful life	15 years
Tower portfolio \| Assigned sites \| Transaction agreement with EIP holdings
Disposition
Consideration received	$ 153,400
Tower portfolio \| Managed sites \| Transaction agreement with EIP holdings
Disposition
Consideration received	114,300
Tower portfolio \| Deferred sites \| Transaction agreement with EIP holdings
Disposition
Contingent consideration receivable	$ 29,600
India solar investment \| Held-for-sale
Disposition
Equity method investment impairment amount					2,600
Assets held for sale			$ 8,600	$ 8,600	$ 8,600