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Sole-Source Cost-Sharing Agreement - Additional Information (Detail) - USAMRMC - USD ($) |  | 1 Months Ended | 3 Months Ended
--- | --- | --- | ---
Nov. 07, 2017 | Jul. 31, 2015 | Mar. 31, 2018 | Sep. 30, 2017
Schedule Of Cost Sharing Agreement [Line Items] |  |  |  |
Expiration date of original contract |  |  | Dec. 31, 2016 |
Reimbursement received |  |  | $ 3,000,000 |
Reimbursement received recorded as advance against final milestone |  |  | $ 200,000 |
Extended expiration date of original contract | Dec. 31, 2018 |  |  |
Maximum |  |  |  |
Schedule Of Cost Sharing Agreement [Line Items] |  |  |  |
Reimbursable trial cost |  | $ 3,000,000 |  |
Cooperative Research and Development Agreement |  |  |  |
Schedule Of Cost Sharing Agreement [Line Items] |  |  |  |
Extended expiration date of original contract |  |  |  | Dec. 31, 2021
Expiration year of original contract |  |  |  | 2018

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- Definition Cost associated with reimbursable income. This occurs when a services entity incurs expenses on behalf of the client and passes through the cost of reimbursable expenses to a client. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 45 -Section 45 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=68075638&loc=d3e60722-111653 + Details
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