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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585

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Restructuring Expenses - Narrative (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2018
Q4 2018 Restructuring Plan \| Employee severance
Restructuring Cost and Reserve [Line Items]
Restructuring expenses		$ 1.3
Q1 2018 Restructuring Plan \| Employee severance
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	$ 1.9
Q1 2018 Restructuring Plan \| Restructuring Cost
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	$ 3.0