The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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GOODWILL AND INTANGIBLE ASSETS - Customer Relationships (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite-lived intangible assets
Amortization of acquisition intangibles	$ 13,016	$ 7,775	$ 1,807
Future Amortization
Total	31,992	44,294
Customer relationships \| International Telecom
Finite-lived intangible assets
Amortization of acquisition intangibles	11,600	7,000	$ 1,500
Future Amortization
2023	827
2024	576
2025	576
2026	576
2027	576
Thereafter	338
Total	3,469
Customer relationships \| US Telecom
Future Amortization
2023	10,248
2024	5,748
2025	2,779
Thereafter	0
Total	18,775
Trade name licenses
Finite-lived intangible assets
Other intangible assets	9,700	$ 10,500
Trade name licenses \| International Telecom
Future Amortization
2023	307
2024	307
2025	307
2026	209
2027	37
Total	1,167
Trade name licenses \| US Telecom
Future Amortization
2023	1,028
2024	964
2025	879
2026	769
2027	718
Thereafter	4,223
Total	$ 8,581