Commitments and Contingencies - Rollforward (Details) - Product Warranty - USD ($) $ in Millions	3 Months Ended	8 Months Ended
Dec. 31, 2018	Dec. 31, 2018
Loss Contingency Accrual
Recall reserve - established April 2018		$ 3.8
Reserve usage		(3.9)
Change in estimate - expense	$ 0.2	0.2
Balance at December 31, 2018	$ 0.1	$ 0.1

Amount of loss contingency liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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- Definition

Amount of cash outflow reducing loss contingency liability.

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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