The percentage of aquiree's stock that will be converted into the cash election option.

No definition available.

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The exchange ratio for exchanging acquiree's common stock to acquior's common stock in a business acquisition.

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No definition available.

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The number of customers that a company has.

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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
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-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
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For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 1
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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to inventory acquired in connection with a business combination for which the initial accounting was incomplete.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 4A
-Subparagraph (c)
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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)(1)
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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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-Paragraph 2
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

Cash outflow representing an adjustment to the purchase price of a previous acquisition.

+ References

No definition available.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
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Note 2 - Acquisitions (Details Textual) $ / shares in Units, $ in Thousands								3 Months Ended
	Aug. 28, 2017 USD ($) $ / shares	Jul. 07, 2017 USD ($)	Mar. 01, 2017 USD ($)	Feb. 28, 2017 USD ($)	Aug. 29, 2016 USD ($)	Apr. 04, 2016 USD ($)	Mar. 25, 2016 USD ($)	Jul. 01, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Electronics [Member]
Goodwill, Acquired During Period							$ 103,800
Automotive [Member]
Goodwill, Acquired During Period							61,300
Monolith [Member]
Cost Method Investments									$ 3,500	$ 3,500
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners										12.00%
IXYS Corporation [Member]
Business Acquisition, Share Price \| $ / shares	$ 23
Business Acquisition, Share Exchange Ratio	0.1265
Business Acquisition, Cash Election Option, Percentage	50.00%
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 750,000
U.S. Sensor [Member]
Payments to Acquire Businesses, Gross		$ 24,439
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory		$ 1,600
Monolith [Member]
Business Acquisition, Percentage of Voting Interests Acquired				62.00%
Business Combination, Consideration Transferred				$ 15,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low				1,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				10,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value			$ 3,500	$ 3,500
ON Portfolio [Member]
Payments to Acquire Businesses, Gross					$ 104,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory					700
Business Combination, Consideration Transferred					104,000
Business Acquisition, Goodwill, Expected Tax Deductible Amount					$ 7,300
ON Portfolio [Member] \| Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life					13 years 182 days
ON Portfolio [Member] \| Patented and Unpatented Technologies [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life					6 years
ON Portfolio [Member] \| Patented and Unpatented Technologies [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life					8 years 182 days
ON Portfolio [Member] \| Noncompete Agreements [Member]
Finite-Lived Intangible Asset, Useful Life					4 years
Menber's S.p.A. [Member]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory						$ 200
Business Combination, Consideration Transferred						$ 19,200
Menber's S.p.A. [Member] \| Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life						10 years
Menber's S.p.A. [Member] \| Patented and Unpatented Technologies [Member]
Finite-Lived Intangible Asset, Useful Life						5 years
Menber's S.p.A. [Member] \| Trademarks and Trade Names [Member]
Finite-Lived Intangible Asset, Useful Life						10 years
PolySwitch [Member]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory							$ 6,900
Business Acquisition, Percentage of Voting Interests Acquired							100.00%
Business Combination, Consideration Transferred							$ 348,292
Business Acquisition, Goodwill, Expected Tax Deductible Amount							$ 64,900
Payments for Previous Acquisition								$ 3,800
PolySwitch [Member] \| Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life							15 years
PolySwitch [Member] \| Patented and Unpatented Technologies [Member]
Finite-Lived Intangible Asset, Useful Life							10 years
IXYS Corporation [Member]
Number of Customers	3,500