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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Workforce Reduction - General Information (Details) $ in Thousands		3 Months Ended
	Feb. 07, 2019 employee	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Restructuring expenses
Restructuring expenses		$ 0	$ 3,328
Restructuring accruals		$ 200		$ 200
Reduction in Workforce, February 7, 2019
Workforce Reduction
Number of employees expected to be eliminated \| employee	35
Restructuring expenses
Employee severance, benefits and related costs			$ 3,300