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LONG-TERM DEBT - Debt Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
LONG-TERM DEBT
Long-term Debt	$ 579,606	$ 557,356
Total Debt
LONG-TERM DEBT
October 1, 2025 through December 31, 2025	2,548
Year ending December 31, 2026	15,844
Year ending December 31, 2027	27,348
Year ending December 31, 2028	108,228
Year ending December 31, 2029	385,937
Thereafter	49,739
Total	589,644
Debt Discounts	(10,038)
Long-term Debt	579,606
Customer Receivable Credit Facility
LONG-TERM DEBT
October 1, 2025 through December 31, 2025	1,908
Year ending December 31, 2026	8,409
Year ending December 31, 2027	8,807
Year ending December 31, 2028	9,229
Year ending December 31, 2029	6,041
Thereafter	4,085
Total	38,479
Debt Discounts	(281)
Long-term Debt	38,198
Corporate and Other
LONG-TERM DEBT
October 1, 2025 through December 31, 2025	1,625
Year ending December 31, 2026	8,125
Year ending December 31, 2027	9,750
Year ending December 31, 2028	84,870
Year ending December 31, 2029	93,438
Total	197,808
Debt Discounts	(2,706)
Long-term Debt	195,102	181,265
US Telecom | Operating segments
LONG-TERM DEBT
Long-term Debt	324,578	316,241
US Telecom | Operating segments | Total Debt
LONG-TERM DEBT
October 1, 2025 through December 31, 2025	923
Year ending December 31, 2026	5,469
Year ending December 31, 2027	13,098
Year ending December 31, 2028	18,858
Year ending December 31, 2029	287,249
Thereafter	6,239
Total	331,836
Debt Discounts	(7,258)
Long-term Debt	324,578
International Telecom | Operating segments
LONG-TERM DEBT
Long-term Debt	59,926	$ 59,850
International Telecom | Operating segments | Total Debt
LONG-TERM DEBT
Year ending December 31, 2026	2,250
Year ending December 31, 2027	4,500
Year ending December 31, 2028	4,500
Year ending December 31, 2029	5,250
Thereafter	43,500
Total	60,000
Debt Discounts	(74)
Long-term Debt	$ 59,926

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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