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, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-lived intangible assets
Amortization of acquisition intangibles	$ 7,775	$ 1,807	$ 2,162
Future Amortization
Total	44,294	6,995
Customer relationships \| International Telecom
Finite-lived intangible assets
Amortization of acquisition intangibles	7,000	1,500	$ 1,800
Future Amortization
2022	1,143
2023	827
2024	576
2025	576
2026	576
Thereafter	915
Total	4,613
Customer relationships \| US Telecom
Future Amortization
2022	10,424
2023	10,248
2024	5,748
2025	2,778
Thereafter	0
Total	29,198
Trade name licenses
Finite-lived intangible assets
Other intangible assets	10,500	$ 1,100
Trade name licenses \| International Telecom
Future Amortization
2022	307
2023	307
2024	307
2025	307
2026	208
Thereafter	38
Total	1,474
Trade name licenses \| US Telecom
Future Amortization
2022	984
2023	936
2024	876
2025	816
2026	708
Thereafter	4,688
Total	$ 9,008