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Significant Accounting Policies - Additional Information (Detail) | 6 Months Ended
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Jun. 30, 2019
Accounting Policies [Abstract] |
Cash and cash equivalents maturity period, maximum | 90 days
Short-term lease exception - Lease term | 12 months

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- References No definition available. + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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Balance Type: | na
Period Type: | instant

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- Definition Cash and cash equivalents criteria maturity period. + References No definition available. + Details
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