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The Company and its Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 01, 2019 | Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Company And Significant Accounting Policies [Line Items] |  |  |  |  |
Entity incorporation date |  | Aug. 05, 1999 |  |  |
Cash and cash equivalents |  | $ 12,362 |  | $ 11,298 |
Net loss from operations |  | 9,964 | $ 5,124 |  |
Increase in cash balance |  | $ 1,064 |  |  |
IPO closing date |  | May 14, 2019 |  |  |
Deferred revenue as contract liabilities |  | $ 306 |  | $ 291 |
ASC 606 |  |  |  |  |
Company And Significant Accounting Policies [Line Items] |  |  |  |  |
Cumulative effect adjustment net of associated tax effect to reduce accumulated deficit | $ 3,115 |  |  |  |
Cumulative effect adjustment associated tax effect to reduce accumulated deficit | 215 |  |  |  |
Deferred revenue as contract liabilities | $ 770 |  |  |  |
Common Stock | IPO |  |  |  |  |
Company And Significant Accounting Policies [Line Items] |  |  |  |  |
Deferred offering costs |  |  | $ 1,709 |  | $ 63

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