Restructuring Expenses - Narrative (Details) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
Feb. 28, 2019 employee	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)
Restructuring and Related Activities [Abstract]
Employees displaced through workforce reduction \| employee	110
Restructuring charges \| $		$ 0	$ 7,420	$ 0	$ 7,420	$ 0

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Period Type:	duration