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Accounting Policies - Additional Information (Detail) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) segment | Jan. 01, 2019 USD ($)
Accounting Policies [Line Items] |  |
Maturity period of liquid investments | 3 months |
Maturity period of financial instruments | Greater than three months and less than one year |
Number of operating segments | segment | 1 |
Right-of-use assets | $ 329 |
ASU 2016-02 [Member] |  |
Accounting Policies [Line Items] |  |
Right-of-use assets |  | $ 500
Operating lease liability |  | $ 500
Restricted Stock Unit Awards [Member] |  |
Accounting Policies [Line Items] |  |
Award vesting period | 4 years |

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- Definition Accounting policies. + References No definition available. + Details
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- Definition Description of maturity period of financial instruments to be considered as short term investment. + References No definition available. + Details
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- Definition Maturity period of highly liquid investments to be considered as cash equivalent. + References No definition available. + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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