Commitment and Contingencies - Narratives (Details) - USD ($) $ in Millions		6 Months Ended
Apr. 23, 2018	Jun. 30, 2018
Contingencies
Warranty expense		$ 3.5
Commitment and Contingencies
Contingencies
Warranty expense	$ 3.8

Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Name:	us-gaap_StandardProductWarrantyAccrualWarrantiesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration