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Investments - Additional Information (Detail) - Investment Penny Warrants [Member] - Fisker Inc. [Member] shares in Millions, $ in Millions	1 Months Ended
	Oct. 31, 2020 USD ($) shares
Schedule of Equity Method Investments [Line Items]
Equity Method Investment Number of warrants subscribed | shares	19.5
Vested During 2021 and 2022 [Member]
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Equity Securities, FV-NI | $	$ 320

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Amount of cash outflow to acquire investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as investing activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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