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Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Oct. 01, 2017 | Jul. 02, 2017 | Apr. 02, 2017 | Dec. 31, 2016 | Oct. 02, 2016 | Jul. 03, 2016 | Apr. 03, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring and other-employee severance |  | $ 8,970 | [1],[2] | $ (4,407) | [3] | $ 2,288 | [2],[4] | $ 2,511 | [5] | $ 5,570 | [6],[7] | $ 12,177 | [7],[8] | $ 2,608 | [7],[9] | $ 1,587 | [7],[10] | $ 9,362 | $ 21,942 | $ 5,080
Goodwill impairment charge |  |  |  |  |  |  |  |  |  | 0 |  |  |  | 254,946 | [7],[9] |  |  | 0 | 254,946 |
Intangible assets impairment charge |  |  |  |  |  |  |  |  |  |  |  |  |  | 83,339 | [7],[9] |  |  |  | 83,339 |
Pension acturial (gains) losses |  | 3,800 |  |  |  | 2,500 |  |  |  | 2,000 |  | (700) |  | 700 |  | 1,200 |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,820 | 15,896 | 2,489
Other (income) expense, net-gain from the sale of an equity investment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,406
Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Building impairment and other expenses |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,200 |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400 |  |  |  |  |  |
Universal Robots |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  | $ 6,000 |  | $ (300) |  | $ 1,500 |  | $ 600 |  | $ 5,400 |  | $ 8,000 |  |  |  | $ 1,200 |  | 7,800 | 15,300 | 5,300
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000
Universal Robots | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  | 800 |  |  |  |  |  |
ZTEC Instruments, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (1,600)
Avionics Interface Technologies, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 600 | (1,300)
Avionics Interface Technologies, LLC | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  | 600 |  |  |  |  |  |
Semiconductor Test |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of revenues-inventory charge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,606 | 9,656 | 10,508
Semiconductor Test | Fixed Assets [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring and other-employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,124 |  |
Semiconductor Test | Severance And Benefits |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring and other-employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,779 | 2,860 | 499
System Test |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of revenues-inventory charge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,918 | 630 | 8,324
Restructuring and other-employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (49) | 1,037
Industrial Automation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring and other-employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,414 | 585 |
Cost of revenues-inventory step-up | [11] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,567
Wireless Test |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of revenues-inventory charge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,190 | 7,207 | 2,500
Restructuring and other-lease impairment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 973 |  |
Restructuring and other-employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,650 |
Goodwill impairment charge |  |  |  |  |  |  |  |  |  |  |  |  |  | 254,900 |  |  |  |  | 254,946 |
Intangible assets impairment charge |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 83,300 |  |  |  |  | 83,339 |
Corporate And Eliminations | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restructuring and other-employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 530 |  |
Property insurance recovery |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (5,064) | (5,051) |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,104
Corporate And Eliminations | Cost of revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension acturial (gains) losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2,752) | (1,025) | 8,271
Corporate And Eliminations | Engineering and development |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension acturial (gains) losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2,456) | (1,234) | 4,658
Corporate And Eliminations | Selling and administrative |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension acturial (gains) losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (1,416) | (944) | 4,826
Corporate And Eliminations | Other (income) expense, net |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other (income) expense, net-gain from the sale of an equity investment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (5,406)
Corporate And Eliminations | Universal Robots | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,820 | 15,346 | 5,339
Corporate And Eliminations | Impairment of fixed assets and expenses related to the Japan earthquake | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Building impairment and other expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 755 | 5,051 |
Corporate And Eliminations | ZTEC Instruments, Inc. | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (1,600)
Corporate And Eliminations | Avionics Interface Technologies, LLC | Restructuring and other |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 550 | $ (1,250)
[1] | Restructuring and other includes a $6.0 million fair value adjustment to increase the Universal Robots acquisition contingent consideration, $1.8 million of employee severance charges, and $1.1 million of charges for impairment of fixed assets.
[2] | Teradyne recorded pension and post retirement net actuarial gains of $2.5 million and $3.8 million for the second and fourth quarter in 2017, respectively. See Note B: "Accounting Policies" for a discussion of Teradyne's accounting policy.
[3] | Restructuring and other includes $5.1 million of property insurance recovery related to the Japan earthquake, a $0.4 million credit related to previously impaired lease termination of a Wireless Test facility in Sunnyvale, CA, and a $0.3 million credit for the decrease in the fair value of the Universal Robots contingent consideration liability, partially offset by $0.8 million of Japan earthquake related expenses and $0.6 million of employee severance charges.
[4] | Restructuring and other includes a $1.5 million charge for a fair value adjustment to increase the Universal Robots acquisition contingent consideration, and $0.8 million of employee severance charges.
[5] | Restructuring and other includes a $1.3 million charge for a lease impairment of a Wireless Test facility in Sunnyvale, CA, a $0.6 million fair value adjustment to increase the Universal Robots acquisition contingent consideration, and $0.6 million of employee severance charges.
[6] | Restructuring and other includes a $5.4 million fair value adjustment to increase the Universal Robots acquisition contingent consideration.
[7] | Teradyne recorded pension and post retirement net actuarial (gains) losses of $(1.2) million, $(0.7) million, $0.7 million and $(2.0) million for the first, second, third, and fourth quarter in 2016, respectively. See Note B: "Accounting Policies" for a discussion of Teradyne's accounting policy.
[8] | Restructuring and other includes an $8.0 million fair value adjustment to increase the Universal Robots acquisition contingent consideration.
[9] | Restructuring and other includes $4.2 million for an impairment of fixed assets, $0.9 million for expenses related to an earthquake in Kumamoto, Japan, and a $1.4 million fair value adjustment to increase contingent consideration liability, of which $0.8 million was related to Universal Robots and $0.6 million was related to AIT, partially offset by $5.1 million of property insurance recovery related to the Japan earthquake.
[10] | Restructuring and other includes a $1.2 million fair value adjustment to increase the Universal Robots acquisition contingent consideration.
[11] | Included in the cost of revenues for the year ended December 31, 2015 is the cost for purchase accounting inventory step-up.

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