Financial instruments.

No definition available.

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- Definition

The maximum length of time, in years, that the amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer, are in a continuous unrealized loss/gain position.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financial Instruments [Line Items]
Period cash equivalents and short-term investments have been in continuous unrealized gain (loss) position, years, maximum	1 year
Total short-term investments (available for sale), Fair value	$ 300,676	$ 185,488
CCKF [Member]
Financial Instruments [Line Items]
Non controlling interest	$ 3,200
Percentage of investment in equity affiliate	30.70%
Maximum [Member] \| CCKF [Member]
Financial Instruments [Line Items]
Gain (loss) from investment in affiliate	$ 200	100	$ (400)
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Instruments [Line Items]
Total short-term investments (available for sale), Fair value	1,700	$ 36,600
Certificate Of Deposit Commercial Paper And Treasury Bills [Member] \| Level 2 [Member]
Financial Instruments [Line Items]
Total short-term investments (available for sale), Fair value	$ 5,100