v3.20.2

Summary of Significant Accounting Policies and Other Information - Narrative (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Apr. 30, 2020 USD ($) | Sep. 30, 2020 USD ($) board_member | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) board_member segment | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($)
Concentration Risk [Line Items] |  |  |  |  |  |
Number of board members | board_member |  | 3 |  | 3 |  |
Number of operating segments | segment |  |  |  | 1 |  |
Research and development and engineering expenses |  | $ 6,200,000 | $ 5,900,000 | $ 18,200,000 | $ 17,400,000 |
Outstanding letters of credit amount |  | 2,800,000 |  | 2,800,000 |  |
Restricted cash |  | $ 3,299,000 | $ 0 | $ 3,299,000 | $ 0 | $ 0
Revolving Credit Facility | Standard Chartered Bank Credit Agreement |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Borrowing amount | $ 130,000,000.0 |  |  |  |  |
Maturity period prior to the final maturity of unsecured senior notes | 60 days |  |  |  |  |
Extension fee percentage | 0.25% |  |  |  |  |

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