Restructuring (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Restructuring [Abstract]
Non-cash impairment charges			$ 48,600
Cash charges associated with restructuring			22,100
Employee severance			20,100
Other related restructuring charges			2,000
Restructuring Reserve [Roll Forward]
Beginning balance		$ 15,462
Amounts paid		(15,046)
Adjustments		(416)
Ending balance		$ 0	$ 15,462
Restructuring activity	$ 0

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of increase (decrease) in the restructuring reserve related to foreign currency translation (gain) loss and other increases (decreases).

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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