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Business and Significant Accounting Policies - Additional Information (Details) - Customer | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
ASU 2016-13 |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] | true |  | true |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | Jan. 01, 2020 |  | Jan. 01, 2020 |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] | true |  | true |  |
ASU 2018-15 |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] | true |  | true |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | Jan. 01, 2020 |  | Jan. 01, 2020 |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] | true |  | true |  |
ASU 2020-04 |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] | true |  | true |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | Mar. 12, 2020 |  | Mar. 12, 2020 |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] | true |  | true |  |
Accounts Receivables | Customer Concentration Risk |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Concentration risk, percentage |  |  |  |  | 10.00%
Number of customers |  |  | 1 |  | 1
Revenues | Customer Concentration Risk |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Concentration risk, percentage | 10.00% | 10.00% | 10.00% | 10.00% |
Number of customers | 2 | 2 | 2 | 2 |
Minimum |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Collection period for trade accounts receivable |  |  | 30 days |  |
Maximum |  |  |  |  |
Business And Significant Accounting Policies [Line Items] |  |  |  |  |
Collection period for trade accounts receivable |  |  | 60 days |  |

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