Number of joint ventures.

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- Definition

Related party transaction license income.

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- Definition

The amount of assets reported by an equity method investment of the entity.

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The amount of liabilities reported by an equity method investment of the entity.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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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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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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Joint Venture and Related Party Transactions - Additional Information (Detail)	1 Months Ended	12 Months Ended		55 Months Ended
	Jun. 30, 2009 JointVenture	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 31, 2014 USD ($)
Related Party Transaction [Line Items]
Number of joint venture agreements \| JointVenture	2
License agreement payment				$ 18,750,000
TVaura LLC [Member]
Related Party Transaction [Line Items]
Equity method investment, ownership percentage	51.00%
Investment in joint venture		$ 0	$ 0
Joint ventures revenue or expenses		0	0
Joint ventures assets		0	0
Joint ventures liability		0	0
TVaura Mobile LLC [Member]
Related Party Transaction [Line Items]
Equity method investment, ownership percentage	49.00%
Investment in joint venture		0	0
Joint ventures revenue or expenses		0	0
Joint ventures assets		0	0
Joint ventures liability		$ 0	$ 0