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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Goodwill and Definite and Indefinite-lived Intangible Assets - Additional Information (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
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 1,114	$ 875	$ 1,969	$ 1,756
Intangible assets, net	$ 62,725		$ 62,725		$ 48,857
Indefinite-lived and Finite-Lived Intangible Assets \| Total assets
Finite-Lived Intangible Assets [Line Items]
Percentage of total assets			7.00%