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Note 2 - Acquisitions and Dispositions - Preliminary Price Allocation (Details) - USD ($) $ in Thousands |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 07, 2017 | Mar. 01, 2017 | Feb. 28, 2017 | Aug. 29, 2016 | Apr. 04, 2016 | Mar. 25, 2016 | Oct. 01, 2015 | Dec. 30, 2017 | Dec. 31, 2016 | Jan. 02, 2016
Goodwill |  |  |  |  |  |  |  | $ 453,414 | $ 403,544 | $ 189,767
Cash, net of cash acquired |  |  |  |  |  |  |  | $ 38,512 | $ 471,118 | $ 4,558
U.S. Sensor [Member] |  |  |  |  |  |  |  |  |  |
Cash | $ 24,340 |  |  |  |  |  |  |  |  |
Current assets, net | 4,635 |  |  |  |  |  |  |  |  |
Goodwill | 16,075 |  |  |  |  |  |  |  |  |
Current liabilities | (540) |  |  |  |  |  |  |  |  |
| 24,340 |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses, Gross | 24,340 |  |  |  |  |  |  |  |  |
U.S. Sensor [Member] | Patented and Unpatented Technologies [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill | 1,090 |  |  |  |  |  |  |  |  |
U.S. Sensor [Member] | Customer Relationships [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill | 2,830 |  |  |  |  |  |  |  |  |
U.S. Sensor [Member] | Trademarks and Trade Names [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill | 200 |  |  |  |  |  |  |  |  |
U.S. Sensor [Member] | Noncompete Agreements [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill | $ 50 |  |  |  |  |  |  |  |  |
Monolith [Member] |  |  |  |  |  |  |  |  |  |
Current assets, net |  | $ 891 |  |  |  |  |  |  |  |
Goodwill |  | 20,641 |  |  |  |  |  |  |  |
Current liabilities |  | (639) |  |  |  |  |  |  |  |
Original investment |  | 3,500 | $ 3,500 |  |  |  |  |  |  |
Cash, net of cash acquired |  | 14,172 |  |  |  |  |  |  |  |
Fair value of commitment to purchase non-controlling interest |  | 9,000 |  |  |  |  |  |  |  |
Total purchase consideration |  | 26,672 |  |  |  |  |  |  |  |
Property, plant, and equipment |  | 789 |  |  |  |  |  |  |  |
Other non-current liabilities |  | (1,870) |  |  |  |  |  |  |  |
|  | 26,672 |  |  |  |  |  |  |  |
Total purchase consideration |  |  | $ 15,000 |  |  |  |  |  |  |
Monolith [Member] | Patented and Unpatented Technologies [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  | 6,720 |  |  |  |  |  |  |  |
Monolith [Member] | Noncompete Agreements [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  | $ 140 |  |  |  |  |  |  |  |
ON Portfolio [Member] |  |  |  |  |  |  |  |  |  |
Cash |  |  |  | $ 104,000 |  |  |  |  |  |
Current assets, net |  |  |  | 4,816 |  |  |  |  |  |
Goodwill |  |  |  | 56,084 |  |  |  |  |  |
|  |  |  | 104,000 |  |  |  |  |  |
Total purchase consideration |  |  |  | 104,000 |  |  |  |  |  |
Payments to Acquire Businesses, Gross |  |  |  | 104,000 |  |  |  |  |  |
ON Portfolio [Member] | Patented and Unpatented Technologies [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  | 8,800 |  |  |  |  |  |
ON Portfolio [Member] | Customer Relationships [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  | 31,800 |  |  |  |  |  |
ON Portfolio [Member] | Noncompete Agreements [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  | $ 2,500 |  |  |  |  |  |
Menber's S.p.A. [Member] |  |  |  |  |  |  |  |  |  |
Current assets, net |  |  |  |  | $ 12,919 |  |  |  |  |
Goodwill |  |  |  |  | 8,091 |  |  |  |  |
Current liabilities |  |  |  |  | (7,220) |  |  |  |  |
|  |  |  |  | 19,162 |  |  |  |  |
Cash, net of cash acquired |  |  |  |  | 19,162 |  |  |  |  |
Property, plant, and equipment |  |  |  |  | 1,693 |  |  |  |  |
Other non-current liabilities |  |  |  |  | (1,444) |  |  |  |  |
Total purchase consideration |  |  |  |  | 19,200 |  |  |  |  |
Menber's S.p.A. [Member] | Patented and Unpatented Technologies [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  |  | 224 |  |  |  |  |
Menber's S.p.A. [Member] | Customer Relationships [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  |  | 3,050 |  |  |  |  |
Menber's S.p.A. [Member] | Trademarks and Trade Names [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  |  | $ 1,849 |  |  |  |  |
PolySwitch [Member] |  |  |  |  |  |  |  |  |  |
Current assets, net |  |  |  |  |  | $ 60,228 |  |  |  |
Goodwill |  |  |  |  |  | 165,088 |  |  |  |
Current liabilities |  |  |  |  |  | (35,280) |  |  |  |
|  |  |  |  |  | 348,292 |  |  |  |
Property, plant, and equipment |  |  |  |  |  | 51,613 |  |  |  |
Other non-current liabilities |  |  |  |  |  | (5,020) |  |  |  |
Original consideration |  |  |  |  |  | 350,000 |  |  |  |
Post closing consideration adjustment received |  |  |  |  |  | (1,708) |  |  |  |
Acquired cash |  |  |  |  |  | (3,810) |  |  |  |
Acquired cash to be returned to seller |  |  |  |  |  | 3,810 |  |  |  |
Total purchase consideration |  |  |  |  |  | 348,292 |  |  |  |
Land lease |  |  |  |  |  | 4,290 |  |  |  |
Other long-term assets |  |  |  |  |  | 11,228 |  |  |  |
Estimated additional consideration payable |  |  |  |  |  | 3,810 |  |  |  |
PolySwitch [Member] | Patented and Unpatented Technologies [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  |  |  | 56,425 |  |  |  |
PolySwitch [Member] | Customer Relationships [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  |  |  | $ 39,720 |  |  |  |
Sigmar [Member] |  |  |  |  |  |  |  |  |  |
Cash |  |  |  |  |  |  | $ 5,558 |  |  |
Current assets, net |  |  |  |  |  |  | 2,519 |  |  |
Goodwill |  |  |  |  |  |  | 4,084 |  |  |
Current liabilities |  |  |  |  |  |  | (1,518) |  |  |
|  |  |  |  |  |  | 6,459 |  |  |
Property, plant, and equipment |  |  |  |  |  |  | 1,097 |  |  |
Other non-current liabilities |  |  |  |  |  |  | (2,568) |  |  |
Acquired cash to be returned to seller |  |  |  |  |  |  | 901 |  |  |
Total purchase consideration |  |  |  |  |  |  | 6,459 |  |  |
Payments to Acquire Businesses, Gross |  |  |  |  |  |  | 5,558 |  |  |
Estimated additional consideration payable |  |  |  |  |  |  | 901 |  |  |
Sigmar [Member] | Patents [Member] |  |  |  |  |  |  |  |  |  |
Intangible assets, other than goodwill |  |  |  |  |  |  | $ 2,845 |  |  |

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