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Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] $ in Thousands | Jun. 30, 2018 USD ($)
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Assets |
Total assets | $ 15,330
Cash [Member] |
Assets |
Total assets | 1,083
Money market securities (cash equivalents) [Member] |
Assets |
Total assets | 14,197
Restricted cash [Member] |
Assets |
Total assets | 50
Level 1 [Member] |
Assets |
Total assets | 15,330
Level 1 [Member] | Cash [Member] |
Assets |
Total assets | 1,083
Level 1 [Member] | Money market securities (cash equivalents) [Member] |
Assets |
Total assets | 14,197
Level 1 [Member] | Restricted cash [Member] |
Assets |
Total assets | $ 50

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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