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GOODWILL AND INTANGIBLE ASSETS - Customer Relationships (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-lived intangible assets
Amortization of intangibles	$ 12,636	$ 13,016	$ 7,775
Future Amortization
Total	19,585	31,992
Customer relationships \| International Telecom
Finite-lived intangible assets
Amortization of intangibles	11,100	11,600	7,000
Future Amortization
2024	576
2025	576
2026	576
2027	576
2028	275
Thereafter	62
Total	2,641
Customer relationships \| US Telecom
Future Amortization
2024	5,748
2025	2,779
Total	8,527
Trade name licenses
Finite-lived intangible assets
Other intangible assets	8,400	9,700
Amortization of intangibles	1,300	$ 1,300	$ 800
Trade name licenses \| International Telecom
Future Amortization
2024	307
2025	307
2026	209
2027	37
Total	860
Trade name licenses \| US Telecom
Future Amortization
2024	964
2025	879
2026	769
2027	718
2028	657
Thereafter	3,570
Total	$ 7,557