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Maximum estimated service period for players.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of consideration paid in advance for advertising that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Principal Activities, Basis of Presentation, and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Maximum estimated service period for players	6 months
Advertising expenses	$ 400	$ 1,200	$ 1,900
Prepaid advertising costs	0	1
Cumulative effect adjustment recorded to accumulated deficit	(1,056)	346
Adjustments Due to Adoption of New Leases Accounting Standard
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustment recorded to accumulated deficit	$ 1,100
Minimum \| Capitalized software development cost
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible assets, useful life	1 year
Maximum \| Capitalized software development cost
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible assets, useful life	3 years
Prepaid Licensing and Royalty Fees \| Minimum
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible assets, useful life	1 year
Prepaid Licensing and Royalty Fees \| Maximum
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible assets, useful life	2 years
Performance Bonds \| Restricted Cash
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Escrow account	$ 531	$ 518