Components of Intangible Assets and Their Estimated Useful Lives at Acquisition Date (Detail) - Mobile Industrial Robots (MiR) $ in Thousands	Apr. 25, 2018 USD ($)
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 37,660
Total intangible assets, estimated useful life, years	6 years 1 month 6 days
Developed technology
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 24,590
Total intangible assets, estimated useful life, years	6 years
Customer Relationships
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 7,360
Total intangible assets, estimated useful life, years	6 years
Trademarks and tradenames
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 5,450
Total intangible assets, estimated useful life, years	7 years
Customer backlog
Business Acquisition [Line Items]
Total intangible assets, fair value	$ 260
Total intangible assets, estimated useful life, years	3 months 18 days