Significant Accounting Policies - Software Costs (Details) - Capitalized software - Maximum	12 Months Ended
Dec. 31, 2018
Intangible assets
Amortization period	3 years
Cost of sales
Intangible assets
Amortization period	3 years
SG&A expense
Intangible assets
Amortization period	3 years

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.

No definition available.

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