Acquisitions - Intangible Assets Acquired (Details) - USD ($) $ in Millions	Apr. 06, 2018	Oct. 05, 2017
4titude Limited
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life of intangible assets		10 years 4 months 24 days
4titude Limited | Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 21.4
Useful life		10 years
4titude Limited | Completed Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 5.2
Useful life		13 years
4titude Limited | Order or Production Backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 0.4
Useful life		1 year
4titude Limited | Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 0.2
Useful life		1 year
Tec-Sem Group AG
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life of intangible assets	8 years 7 months 6 days
Tec-Sem Group AG | Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 0.7
Useful life	9 years
Tec-Sem Group AG | Completed Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 8.4
Useful life	10 years
Tec-Sem Group AG | Order or Production Backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 1.6
Useful life	1 year