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v3.25.1

Segment Information - Schedule of gross written premium by state (Details) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 USD ($) employee | Mar. 31, 2024 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 254.2 | $ 205.6
Number of reportable segments | employee | 1 |
Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 100.00% | 100.00%
California |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 60.4 | $ 55.3
California | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 23.80% | 26.90%
Texas |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 32.5 | $ 30.0
Texas | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 12.80% | 14.60%
New York |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 25.9 | $ 21.0
New York | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 10.20% | 10.20%
Washington |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 13.0 | $ 8.0
Washington | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 5.10% | 3.90%
New Jersey |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 11.7 | $ 9.7
New Jersey | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 4.60% | 4.70%
Illinois |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 11.6 | $ 9.7
Illinois | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 4.60% | 4.70%
Pennsylvania |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 7.0 | $ 5.1
Pennsylvania | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 2.80% | 2.50%
Colorado |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 6.8 | $ 5.9
Colorado | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 2.70% | 2.90%
Georgia |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 6.5 | $ 5.6
Georgia | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 2.60% | 2.70%
Florida |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 6.3 | $ 3.1
Florida | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 2.50% | 1.50%
All other |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 63.1 | $ 49.1
All other | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 24.60% | 23.90%
US |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 244.8 | $ 202.5
US | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 96.30% | 98.50%
Europe and UK |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Amount | $ 9.4 | $ 3.1
Europe and UK | Gross written premium | Geographic Concentration Risk |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
% of GWP | 3.70% | 1.50%

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