FINANCIAL INSTRUMENTS - Realized and Unrealized Gains and Losses (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Adjustments to Carrying Value of Equity Securities without Readily Determinable Fair Value [Abstract]
Upward adjustments (gross unrealized gains)	$ 128,986
Downward adjustments including impairments (gross unrealized losses)	(4,931)
Total	124,055
Adjustments to Carrying Value of Non-Marketable Equity Securities [Abstract]
Realized gains, net, for equity securities sold	27,874
Unrealized gains, net, on equity securities held	124,170
Total gains recognized, net, in other income (expense), net	$ 152,044

Equity Securities without Readily Determinable Fair Value, Annual Amount

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

+ References

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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

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- Definition

Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

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- Definition

Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

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