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GOODWILL AND INTANGIBLE ASSETS - Customer Relationships (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Finite-lived intangible assets
Amortization of intangibles	$ 7,907	$ 12,636	$ 13,016
Future Amortization
Total	11,990	19,585
Customer Relationships \| International Telecom
Finite-lived intangible assets
Amortization of intangibles	6,300	11,100	$ 11,600
Future Amortization
2025	576
2026	576
2027	576
2028	276
2029	62
Total	2,066
Customer Relationships \| US Telecom
Future Amortization
2025	2,779
Total	2,779
Trade names
Finite-lived intangible assets
Amortization of intangibles	1,300
Other intangible assets	7,100	$ 8,400
Trade names \| International Telecom
Future Amortization
2025	311
2026	209
2027	37
Total	557
Trade names \| US Telecom
Future Amortization
2025	879
2026	769
2027	718
2028	657
2029	619
Thereafter	2,946
Total	$ 6,588