Financial Instruments and Fair Value [Line Items]

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- Definition

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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- Definition

Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

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- Definition

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- Definition

Amount of available-for-sale debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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- Definition

This element represents the amount of any change recognized during the period in the high-end of the estimated range of outcomes (undiscounted) of a liability assumed in a business combination arising from an item of contingent consideration.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement.

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Dec. 31, 2013	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financial Instruments and Fair Value [Line Items]
Available-for-sale securities, realized loss			$ 300,000	$ 500,000	$ 400,000
Available-for-sale securities, realized gain			1,100,000	1,600,000	1,700,000
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses			1,350,896,000	732,979,000
Fair market value of investments with unrealized losses greater than one year			141,000,000	2,900,000
Aggregate loss of investments with unrealized losses greater than one year			1,200,000	300,000
Fair market value of investments with unrealized losses less than one year			1,209,900,000	730,100,000
Aggregate loss of investments with unrealized losses less than one year			2,200,000	2,500,000
Unrealized Gain (loss) on contracts			$ (2,900,000)	$ 8,000,000	2,500,000
Proceeds from sale of equity interest	$ 5,400,000	$ 34,200,000			$ 5,406,000
Accounts Receivable \| Customer 1 \| Minimum
Financial Instruments and Fair Value [Line Items]
Concentration risk, percentage			10.00%
Accounts Receivable \| Customer 2 \| Minimum
Financial Instruments and Fair Value [Line Items]
Concentration risk, percentage				10.00%
Equity and Debt Mutual Funds
Financial Instruments and Fair Value [Line Items]
Available for sale securities with out contractual maturity date			$ 23,400,000
Universal Robots
Financial Instruments and Fair Value [Line Items]
Maximum payment per earn-out			25,000,000
Foreign Exchange Contracts
Financial Instruments and Fair Value [Line Items]
Unrealized Gain (loss) on contracts			$ (100,000)	$ (100,000)