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Summary of Significant Accounting Policies - Additional Information (Detail) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jul. 31, 2017 | Dec. 31, 2019 USD ($) Segment | Dec. 31, 2018 USD ($) | Jan. 01, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Cash equivalents maturity |  | three months or less |  |
Cash equivalents |  | $ 13,500,000 | $ 300,000 |
Cash held in a separate restricted bank account |  | 1,097,000 | 1,097,000 |
Transfers of assets and liabilities between Level 1, Level 2, or Level 3 |  | 0 | 0 |
Impairment charge |  | $ 0 |  |
Revenue, practical expedient, incremental cost of obtaining contract [true/false] |  | true |  |
Revenue, practical expedient, remaining performance obligation, description |  | The Company recognizes as an asset the incremental costs of obtaining a contract with a customer if the costs are expected to be recovered. As a practical expedient, the Company recognizes the incremental costs of obtaining a contract as an expense when incurred if the amortization period of the asset that we otherwise would have recognized is one year or less. To date, the Company has not incurred any incremental costs of obtaining a contract with a customer |  |
Description of tax benefit likely to be realized upon settlement |  | greater than 50% |  |
Number of operating segment | Segment |  | 1 |  |
Lease, practical expedients, package |  | true |  |
Lessee, operating lease, existence of option to extend | true | true |  |
Lessee, operating lease, option to extend |  | options to extend the lease when it is reasonably certain that option will be exercised |  |
Operating lease, right-of-use asset |  | $ 17,263,000 |  | $ 15,900,000
Operating lease, lease liability |  | 24,804,000 |  | $ 24,000,000
Bank Account |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Cash held in a separate restricted bank account |  | 50,000 | 50,000 |
Letter of Credit |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Cash |  | $ 1,000,000 | $ 1,000,000 |

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- Definition An element designated to encapsulate any additional information related to cash and cash equivalents not otherwise addressed by the existing taxonomy. Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. + References No definition available. + Details
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631418-115840 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=118262064&loc=SL116631419-115840 + Details
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- Definition Indicates (true false) whether practical expedients are elected for not reassessing whether any expired or existing contract is or contains lease, lease classification for expired or existing lease, and initial direct cost for any existing lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=119364159&loc=SL77916155-209984 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 10 -Section 65 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=119364159&loc=SL77916155-209984 + 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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