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v3.20.4

Geographical Breakdown of Gross Written Premium (Details) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) segment | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) segment | Dec. 31, 2018 USD ($)
Geographical Breakdown of Gross Written Premium |  |  |  |  |  |
Number of reportable segments | segment |  |  | 1 |  | 1 |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 71.2 | $ 38.0 | $ 156.0 | $ 82.7 | $ 115.8 | $ 46.8
Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 100.00% | 100.00% | 100.00% | 100.00% | 100.00% | 100.00%
Texas |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 15.9 | $ 9.3 | $ 36.5 | $ 21.3 | $ 28.6 | $ 13.4
Texas | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 22.30% | 24.50% | 23.40% | 25.80% | 24.70% | 28.60%
California |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 15.6 | $ 9.3 | $ 34.9 | $ 20.6 | $ 29.0 | $ 12.5
California | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 21.90% | 24.50% | 22.40% | 24.90% | 25.00% | 26.70%
New York |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 8.6 | $ 5.0 | $ 18.8 | $ 11.5 | $ 15.8 | $ 7.3
New York | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 12.10% | 13.20% | 12.10% | 13.90% | 13.60% | 15.60%
Georgia |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 3.8 | $ 2.0 | $ 8.7 | $ 4.4 | $ 6.2 | $ 2.2
Georgia | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 5.30% | 5.30% | 5.60% | 5.30% | 5.40% | 4.70%
Illinois |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 3.4 | $ 1.9 | $ 7.6 | $ 3.9 | $ 5.2 | $ 2.5
Illinois | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 4.80% | 5.00% | 4.90% | 4.70% | 4.50% | 5.30%
New Jersey |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 3.0 | $ 1.5 | $ 6.1 | $ 3.4 | $ 4.7 | $ 1.7
New Jersey | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 4.20% | 3.90% | 3.90% | 4.10% | 4.10% | 3.60%
Michigan |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 2.0 | $ 1.1 | $ 4.4 | $ 2.2 | $ 3.2 | $ 0.9
Michigan | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 2.80% | 2.80% | 2.80% | 2.70% | 2.80% | 1.90%
Pennsylvania |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 2.0 | $ 1.0 | $ 3.8 | $ 2.0 | $ 2.7 | $ 1.1
Pennsylvania | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 2.80% | 2.60% | 2.40% | 2.40% | 2.30% | 2.40%
Ohio |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 1.8 | $ 0.9 | $ 4.0 | $ 2.2 | $ 2.9 | $ 1.3
Ohio | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 2.50% | 2.40% | 2.60% | 2.70% | 2.50% | 2.80%
Arizona |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 1.5 | $ 0.8 | $ 3.4 | $ 1.7 | $ 2.5 | $ 0.8
Arizona | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 2.10% | 2.10% | 2.20% | 2.10% | 2.20% | 1.70%
All other |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
Amount | $ 13.6 | $ 5.2 | $ 27.8 | $ 9.5 | $ 15.0 | $ 3.1
All other | Gross written premium | Geographic Concentration Risk |  |  |  |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |  |  |  |
% of GWP | 19.20% | 13.70% | 17.70% | 11.40% | 12.90% | 6.70%

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