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) - International Telecom - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-lived intangible assets
Other intangible assets	$ 4,500
Customer relationships
Finite-lived intangible assets
Amortization	2,400	$ 3,200	$ 2,000
Future Amortization
2019	1,897
2020	1,528
2021	1,300
2022	1,143
2023	828
Thereafter	2,627
Total	9,323
Franchise Rights
Finite-lived intangible assets
Other intangible assets	3,000
Trade names
Finite-lived intangible assets
Other intangible assets	$ 1,500
Impairment of other intangibles			$ 300