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

No definition available.

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- Definition

The fair value as of the acquisition-date of the commitment to purchase noncontrolling interest in the acquiree in a business combination.

+ References

No definition available.

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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, but excluding the value of stock options converted.

+ References

No definition available.

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The percentage of remaining interest in a step acquisition of a business combination.

+ References

No definition available.

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- Definition

The amount of step-up of inventory on the date of the acquisition in a business combination.

+ References

No definition available.

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Represents the value of stock options converted to company’s stock options in a business acquisition.

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No definition available.

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The amortization period for inventory, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The aggregate expense charged against earnings to allocate the cost of inventory previously stepped-up in cost basis in a business acquisition.

+ References

No definition available.

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- Definition

The number of customers that a company has.

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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

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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

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 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.

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- Definition

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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Fair value at acquisition-date of the assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interests issued by the acquirer, including but not limited to, instruments or interests issued or issuable in consideration for the business combination.

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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.

+ References

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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.

+ References

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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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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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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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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- Definition

Face amount or stated value per share of common stock.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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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.

+ References

No definition available.

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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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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

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/disclosureRef
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-Name Accounting Standards Codification
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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Note 2 - Acquisitions (Details Textual) $ / shares in Units, $ in Thousands					1 Months Ended	2 Months Ended	3 Months Ended
	Jan. 17, 2018 USD ($) $ / shares	Jul. 07, 2017 USD ($)	Mar. 01, 2017 USD ($)	Feb. 28, 2017 USD ($)	Apr. 30, 2018 USD ($)	Mar. 31, 2018 USD ($) $ / shares	Mar. 31, 2018 USD ($) $ / shares	Apr. 01, 2017 USD ($)	Dec. 30, 2017 $ / shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Common Stock, Par or Stated Value Per Share \| $ / shares						$ 0.01	$ 0.01		$ 0.01
Share Price \| $ / shares	$ 207.50
Inventory Charge Related to Step-up in Cost Basis							$ 17,896
Payments to Acquire Businesses, Net of Cash Acquired, Total							$ 306,487	$ 14,172
Finite-Lived Intangible Asset, Useful Life
Inventory, Amortization Period							150 days
Order or Production Backlog [Member]
Finite-Lived Intangible Asset, Useful Life							1 year
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 Combination, Consideration Transferred, Excluding Value of Stock Options Converted	$ 814,800
Payments to Acquire Businesses, Gross	380,500
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	434,192
Business Combination, Value of Stock Options Converted to Company’s Stock Options	41,700
Business Combination, Consideration Transferred, Total	856,500
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	49,100
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual						$ 86,300
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual						$ (17,800)
Business Combination, Step Up of Inventory at Acquisition Date	36,900
Inventory Charge Related to Step-up in Cost Basis							$ 17,900
Business Combination, Acquisition Related Costs							38,600
Payments to Acquire Businesses, Net of Cash Acquired, Total	302,865
IXYS Corporation [Member] \| Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs							10,200
IXYS Corporation [Member] \| Employee Stock Option [Member]
Allocated Share-based Compensation Expense, Total	$ 4,500						$ 5,900
U.S. Sensor [Member]
Payments to Acquire Businesses, Gross		$ 24,340
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		1,500
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory		$ 1,600
Monolith [Member]
Business Combination, Consideration Transferred, Total				$ 15,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables				$ 700
Business Acquisition, Percentage of Voting Interests Acquired				62.00%
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low				$ 500
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				5,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value			$ 3,500	3,500
Payments to Acquire Businesses, Net of Cash Acquired, Total			14,172	14,200
Business Combination, Consideration Transferred, Commitment to Purchase Noncontrolling Interest			9,000	9,000
Business Combination, Consideration Transferred, Including Equity Interest in Acquiree Held Prior to Combination, Total			$ 26,672	$ 26,700
Monolith [Member] \| Subsequent Event [Member]
Business Combination, Consideration Transferred, Total					$ 5,000
Business Acquisition, Percentage of Voting Interests Acquired					19.00%
Business Combination, Step Acquisition, Remaining Interest Percentage					19.00%
IXYS Corporation [Member]
Number of Customers	3,500
Common Stock, Par or Stated Value Per Share \| $ / shares	$ 0.01