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Entity Level Information - Percentage of Total Revenues (Details) - Revenues - Customer Concentration | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Customer A |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |
Concentration risk percentage | 25.00% | 16.00% | 31.00% | 15.00%
Customer B |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |
Concentration risk percentage |  | 19.00% |  | 18.00%
Customer C |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |
Concentration risk percentage | 19.00% |  | 20.00% |
Customer D |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |
Concentration risk percentage | 19.00% | 13.00% | 12.00% | 12.00%
Customer E |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |
Concentration risk percentage |  | 33.00% |  | 31.00%

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