Cash, Cash Equivalents, And Short-term Investments, Amortized Cost

No definition available.

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- Definition

Equity Securities, FV-NI, Accumulated Foreign Currency Translation Gain (Loss)

+ References

No definition available.

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- Definition

Equity Securities, FV-NI, Accumulated Unrealized Gain

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

No definition available.

+ Details

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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714

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- Definition

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.

+ References

No definition available.

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Balance Sheet Account Detail - Summary of Cash and Cash Equivalents and Marketable Securities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Cost of equity securities	$ 8,710
Foreign Currency Translation	(2,168)
Gross unrealized gain on equity securities	39,880
Equity securities	46,422
Available-for-sale securities, amortized cost			$ 227,571
Available-for-sale securities, gross unrealized gain			0
Cash, cash equivalents and short-term investments, amortized cost	166,276
Cash, cash equivalents, and short-term investments	203,988		227,571
Equity securities, unrealized gain (loss)	10,500
Accounting Standards Update 2016-01 [Member]
Schedule of Investments [Line Items]
Cumulative effect of new accounting principle in period of adoption		$ 0
Retained Earnings [Member] \| Accounting Standards Update 2016-01 [Member]
Schedule of Investments [Line Items]
Cumulative effect of new accounting principle in period of adoption		17,211	17,200
AOCI Attributable to Parent [Member]
Schedule of Investments [Line Items]
Cumulative effect of new accounting principle in period of adoption		$ (17,211)
AOCI Attributable to Parent [Member] \| Accounting Standards Update 2016-01 [Member]
Schedule of Investments [Line Items]
Cumulative effect of new accounting principle in period of adoption			(17,200)
Bank Deposits [Member]
Schedule of Investments [Line Items]
Available-for-sale, debt securities, amortized cost	14,735
Available-for-sale, debt securities, estimated fair value	14,735
Available-for-sale securities, amortized cost			10,965
Available-for-sale securities, gross unrealized gain			0
Available-for-sale securities			10,965
Money market funds [Member]
Schedule of Investments [Line Items]
Available-for-sale, debt securities, amortized cost	142,745
Available-for-sale, debt securities, estimated fair value	142,745
Available-for-sale securities, amortized cost			216,358
Available-for-sale securities, gross unrealized gain			0
Available-for-sale securities			216,358
Bank certificates of deposit [Member]
Schedule of Investments [Line Items]
Available-for-sale, debt securities, amortized cost	86
Available-for-sale, debt securities, estimated fair value	86
Available-for-sale securities, amortized cost			248
Available-for-sale securities, gross unrealized gain			0
Available-for-sale securities			248
Cash and Cash Equivalents [Member]
Schedule of Investments [Line Items]
Cash, cash equivalents, and short-term investments	157,480		227,323
Cash and Cash Equivalents [Member] \| Bank Deposits [Member]
Schedule of Investments [Line Items]
Available-for-sale, debt securities, estimated fair value	14,735
Available-for-sale securities			10,965
Cash and Cash Equivalents [Member] \| Money market funds [Member]
Schedule of Investments [Line Items]
Available-for-sale, debt securities, estimated fair value	142,745
Available-for-sale securities			216,358
Marketable Securities [Member]
Schedule of Investments [Line Items]
Equity securities	46,422
Cash, cash equivalents, and short-term investments	46,508		248
Marketable Securities [Member] \| Bank certificates of deposit [Member]
Schedule of Investments [Line Items]
Available-for-sale, debt securities, estimated fair value	$ 86
Available-for-sale securities			$ 248