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.

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

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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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- Definition

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.

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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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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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No definition available.

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

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

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No definition available.

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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 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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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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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

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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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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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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No definition available.

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- Definition

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

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No definition available.

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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.

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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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Acquisitions - Narrative (Details) $ / shares in Units, $ in Thousands						1 Months Ended	3 Months Ended	5 Months Ended	9 Months Ended
	Oct. 05, 2018 USD ($)	Jan. 17, 2018 USD ($) customer $ / shares	Jul. 07, 2017 USD ($)	Mar. 01, 2017 USD ($)	Feb. 28, 2017 USD ($)	Apr. 30, 2018 USD ($)	Sep. 29, 2018 USD ($) $ / shares	Jun. 30, 2018 USD ($)	Sep. 29, 2018 USD ($) $ / shares	Sep. 30, 2017 USD ($)	Dec. 30, 2017 $ / shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Business Acquisition [Line Items]
Common stock, par value (in dollars per share) \| $ / shares							$ 0.01		$ 0.01		$ 0.01
Non-cash inventory charges									$ 36,927	$ 1,607
Cash, net of cash acquired									313,475	38,610
Non-cash, fair value of commitment to purchase non-controlling interest									$ 5,000	$ 9,000
Inventory amortization period									5 months
IXYS Corporation
Business Acquisition [Line Items]
Number of customers \| customer		3,500
Common stock, par value (in dollars per share) \| $ / shares		$ 0.01
Share price (in dollars per share) \| $ / shares		$ 23
Share exchange ratio		0.1265
Share price (in dollars per share) \| $ / shares		$ 207.5
Consideration excluding value of stock options converted		$ 814,800
Cash		380,600
Littelfuse stock		434,192
Value of options converted		41,700
Consideration transferred		856,500
Receivables		49,100
Revenue of acquiree since acquisition							$ 99,700	$ 286,200
Earnings (loss) of acquiree since acquisition							6,200	$ (25,500)
Step-up of inventory at acquisition		36,900
Cash, net of cash acquired		302,865
IXYS Corporation \| Selling, General and Administrative Expenses
Business Acquisition [Line Items]
Allocated share based compensation		$ 4,500					$ 4,300		$ 11,800
Acquisition related costs									$ 11,000
U.S. Sensor
Business Acquisition [Line Items]
Cash			$ 24,340
Receivables			1,500
Inventory adjustment			$ 1,600
Monolith
Business Acquisition [Line Items]
Consideration transferred					$ 15,000	$ 5,000
Receivables					$ 700
Cost method investments												$ 3,500	$ 3,500
Ownership percentage by noncontrolling owners													12.00%
Voting interest acquired					62.00%	19.00%
Original investment				$ 3,500
Cash, net of cash acquired				14,172	$ 14,200
Non-cash, fair value of commitment to purchase non-controlling interest				9,000	9,000
Total purchase consideration				$ 26,672	$ 26,700
Monolith \| Stockholders of Monolith
Business Acquisition [Line Items]
Consideration transferred						$ 4,000
Monolith \| Subsequent Event
Business Acquisition [Line Items]
Consideration transferred	$ 5,000
Voting interest acquired	19.00%