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Summary of Significant Accounting Policies - Additional Information1 (Detail) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-01-01 | Dec. 31, 2018
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Minimum [Member] |
Summary Of Significant Accounting Policy [Line Items] |
Performance obligation, revenue expected to be recognized | 12 months
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Summary Of Significant Accounting Policy [Line Items] |
Performance obligation, revenue expected to be recognized | 24 months

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- Definition Summary Of Significant Accounting Policy [Line Items] + References No definition available. + Details
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- Definition Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045 + Details
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