Business Combinations - 2019 Acquisition Quantum (Details) - Quantum Coating, Inc. $ in Thousands	Oct. 05, 2018 USD ($)
Business Acquisition [Line Items]
Property and equipment	$ 2,770
Total purchase price to allocate	7,000
Existing technology
Business Acquisition [Line Items]
Intangible assets	1,600
Customer relationships
Business Acquisition [Line Items]
Intangible assets	230
Production know-how
Business Acquisition [Line Items]
Intangible assets	2,300
Backlog
Business Acquisition [Line Items]
Intangible assets	$ 100

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The amount of identifiable intangible assets recognized as of the acquisition date.

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-SubTopic 10
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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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