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Basis of Presentation and Summary of Significant Accounting Policies - Capitalized Software Development Costs (Detail) | 12 Months Ended
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Dec. 31, 2017
Basis of Presentation and Summary of Significant Accounting Policies |
Software development cost, amortization period | 2 years

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- Definition Amortization Period Of Capitalized Software Development Costs + References No definition available. + Details
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- References No definition available. + Details
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