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v3.25.4

Segment Information - Gross Written Premium by State (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 1,171.3 | $ 929.0 | $ 738.4
Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 100.00% | 100.00% | 100.00%
California |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 256.8 | $ 225.6 | $ 191.6
California | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 21.90% | 24.30% | 25.90%
Texas |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 148.8 | $ 133.7 | $ 117.5
Texas | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 12.70% | 14.40% | 15.90%
New York |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 116.4 | $ 96.3 | $ 80.8
New York | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 9.90% | 10.40% | 10.90%
Washington |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 60.2 | $ 38.9 | $ 25.9
Washington | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 5.10% | 4.20% | 3.50%
Illinois |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 54.0 | $ 43.7 | $ 35.3
Illinois | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 4.60% | 4.70% | 4.80%
New Jersey |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 52.7 | $ 44.3 | $ 37.6
New Jersey | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 4.50% | 4.80% | 5.10%
Colorado |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 40.9 | $ 29.2 | $ 22.0
Colorado | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 3.50% | 3.10% | 3.00%
Florida |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 33.8 | $ 19.4 | $ 9.3
Florida | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 2.90% | 2.10% | 1.30%
Pennsylvania |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 33.0 | $ 24.9 | $ 19.7
Pennsylvania | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 2.80% | 2.70% | 2.70%
Arizona |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 29.4 | $ 22.4 | $ 18.0
Arizona | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 2.50% | 2.40% | 2.40%
All others |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 299.0 | $ 230.6 | $ 171.4
All others | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 25.60% | 24.70% | 23.20%
United States |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 1,125.0 | $ 909.0 | $ 729.1
United States | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 96.00% | 97.80% | 98.70%
Europe and UK |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Amount | $ 46.3 | $ 20.0 | $ 9.3
Europe and UK | Gross written premium | Geographic Concentration Risk |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
% of GWP | 4.00% | 2.20% | 1.30%

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