Exit Costs, Restructuring Charges and Associated Impairments - Exit Costs Restructuring Charges and Associated Impairment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring And Related Activities [Abstract]
Restructuring charges	$ 0	$ 0	$ 628	$ 1,158
Costs to exit lease and restore facilities	0	0	222	0
Total exit costs, restructuring charges and associated impairments	$ 0	$ 0	$ 850	$ 1,158

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration