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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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GOODWILL AND INTANGIBLE ASSETS - Customer Relationships (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
International
Finite-lived intangible assets
Other intangible assets	$ 4,700
Customer relationships
Finite-lived intangible assets
Amortization	3,200	$ 2,000	$ 400
Customer relationships \| International
Future Amortization
2018	2,411
2019	1,897
2020	1,528
2021	1,300
2022	1,143
Thereafter	3,455
Total	11,734
Franchise Rights \| International
Finite-lived intangible assets
Other intangible assets	3,000
Trade names \| International
Finite-lived intangible assets
Other intangible assets	$ 1,700
Impairment of other intangibles		$ 300