Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Restructuring and other-employee severance	$ 9,312	$ (13,202)	$ (13,880)
Contingent consideration adjustment	(7,227)	(23,271)	(19,257)
Investment impairment	0	0	15,000
Other (income) expense, net—loss on convertible debt conversion	(24,572)	(9,192)	(22,648)
Semiconductor Test
Segment Reporting Information [Line Items]
Acquisition related costs	500	2,500	2,500
Cost of revenues-inventory charge			1,277
Restructuring and other-employee severance	6,661
Contingent consideration adjustment		3,500
Contract termination settlement fee		4,000
Semiconductor Test \| Mobile Industrial Robots (MiR)
Segment Reporting Information [Line Items]
Contingent consideration adjustment			22,200
Semiconductor Test \| Severance And Benefits
Segment Reporting Information [Line Items]
Restructuring and other-employee severance		11,013	8,731
Industrial Automation
Segment Reporting Information [Line Items]
Acquisition related costs	1,000	985	741
Cost of revenues-inventory charge	641	887	2,000
Restructuring and other-employee severance	1,210	1,584	796
Industrial Automation \| Restructuring and other
Segment Reporting Information [Line Items]
Acquisition related costs	(513)	1,728
Industrial Automation \| Severance And Benefits
Segment Reporting Information [Line Items]
Restructuring and other-employee severance			1,765
System Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	6,403	834	508
Wireless Test
Segment Reporting Information [Line Items]
Cost of revenues-inventory charge	1,770	4,800	4,005
Corporate And Eliminations
Segment Reporting Information [Line Items]
Restructuring and other	13,971
Selling and administrative – equity modification charge		766	2,108
Investment impairment			15,000
Corporate And Eliminations \| Restructuring and other
Segment Reporting Information [Line Items]
Other (income) expense, net—loss on convertible debt conversion	28,828
Corporate And Eliminations \| Mobile Industrial Robots (MiR) \| Restructuring and other
Segment Reporting Information [Line Items]
Restructuring and other-lease impairment		(3,546)	(22,199)
Contingent consideration adjustment	$ (7,227)	$ (19,724)	$ 2,976

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Restructuring and other lease impairment.

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Selling and administrative equity modification charge.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The loss recognized on termination of a contract.

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Amount of income (expense) related to nonoperating activities, classified as other.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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