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Basis of Presentation and Summary of Significant Accounting Policies - Capitalized Software Development Costs (Detail)	12 Months Ended
	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

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No definition available.

+ Details

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- References

No definition available.

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