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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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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GOODWILL AND OTHER INTANGIBLE ASSETS - Intangible assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Intangible assets
Amortizing intangibles	$ 66,946		$ 66,946		$ 71,350
Accumulated amortization	(43,340)		(43,340)		(38,311)
Amortizing intangibles, net	23,606		23,606		33,039
Non-amortizing intangibles	1,022,204		1,022,204		1,012,839
Intangibles, net	1,045,810		1,045,810		$ 1,045,878
Amortization expense	$ 3,000	$ 3,000	$ 5,900	$ 6,000
Minimum
Intangible assets
Useful life of intangible assets			5 years
Maximum
Intangible assets
Useful life of intangible assets			7 years