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- Definition

Amount of gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

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- Definition

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

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- Definition

Date the liquidation is expected to be completed, in CCYY-MM-DD format.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

Portion of equity (net assets) in a variable interest entity (VIE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VIE that is attributable to the noncontrolling interest (previously referred to as minority interest).

+ References

No definition available.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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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.

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No definition available.

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Long-Term Investments - Additional Information (Detail) - USD ($)		12 Months Ended
	Sep. 09, 2013	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 20, 2019	Feb. 03, 2009
Schedule Of Equity Method Investments [Line Items]
Fair value of retained noncontrolling interest	$ 55,000,000
Funding commitment letters capped amount		$ 149,000,000
Income (loss) on equity-method investments		$ 1,000,000	$ 8,000,000	$ (2,000,000)
ST-Ericsson SA [Member]
Schedule Of Equity Method Investments [Line Items]
Controlling share held by Ericsson						50.00%
Sale of Stock	1
Deconsolidated gain or loss	$ 0
Liquidation date		Apr. 15, 2014
Income (loss) on equity-method investments		$ 2,000,000	$ 4,000,000
ST-Ericsson SA [Member] \| ST Foundation [Member]
Schedule Of Equity Method Investments [Line Items]
Controlling share held by Ericsson					100.00%
ST-Ericsson SA [Member] \| Maximum [Member]
Schedule Of Equity Method Investments [Line Items]
Income (loss) on equity-method investments				$ 1,000,000