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Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Apr. 01, 2018	Dec. 31, 2018
Financial Instruments and Fair Value [Line Items]
Available-for-sale securities, realized gain	$ 100,000	$ 300,000
Available-for-sale securities, realized loss	100,000	1,500,000
Unrealized loss related to equity securities	2,800,000
Available-for-sale marketable securities, Fair Market Value of Investments in debt securities with Unrealized Losses	120,039,000		$ 191,978,000
Fair market value of investments with unrealized losses greater than one year	32,900,000		28,500,000
Aggregate loss of investments with unrealized losses greater than one year	1,300,000		1,600,000
Fair market value of investments with unrealized losses less than one year	87,100,000		163,500,000
Aggregate loss of investments with unrealized losses less than one year	100,000		1,400,000
Unrealized Gain (loss) on contracts	3,200,000	$ 600,000
Debt Mutual Funds
Financial Instruments and Fair Value [Line Items]
Available for sale securities with out contractual maturity date	3,300,000
Mobile Industrial Robots (MiR)
Financial Instruments and Fair Value [Line Items]
Maximum amount of contingent consideration paid for acquisition	83,200,000
Foreign Exchange Contracts
Financial Instruments and Fair Value [Line Items]
Unrealized Gain (loss) on contracts	$ 148,800,000		$ 163,100,000

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale equity securities.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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