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Summary of Significant Accounting Policies - Additional Information (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 USD ($) shares | Jun. 30, 2019 shares | Jun. 30, 2020 USD ($) Segment shares | Jun. 30, 2019 shares
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Transfers of assets measured on recurring basis out of Level 1 into Level 2 | $ 0 |  | $ 0 |
Transfers of assets measured on recurring basis out of Level 2 into Level 1 | 0 |  | 0 |
Transfers of liabilities measured on recurring basis out of Level 1 into Level 2 | 0 |  | 0 |
Transfers of liabilities measured on recurring basis out of Level 2 into Level 1 | $ 0 |  | 0 |
Transfers of financial instrument classified as liability into level 3 |  |  | 0 |
Transfers of financial instrument classified as liability out of level 3 |  |  | 0 |
Transfers of financial instrument classified as asset into level 3 |  |  | 0 |
Transfers of financial instrument classified as asset out of level 3 |  |  | $ 0 |
Number of operating segment | Segment |  |  | 1 |
Weighted-average shares subject to repurchase or forfeiture | shares | 130,302 | 219,319 | 153,722 | 234,425
Minimum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Estimated useful lives of assets |  |  | 3 years |
Maximum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Estimated useful lives of assets |  |  | 5 years |

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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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
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