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v3.25.1

Related Party Transactions (Details) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 USD ($) director shares | Mar. 31, 2023 $ / shares | Dec. 31, 2020 shares | Dec. 31, 2024 USD ($) shares
Related Party Transaction [Line Items] |  |  |  |
Due from related party (less than for December 31, 2024) | $ 39,400,000 |  |  | $ 42,400,000
Outstanding amounts due (less than for December 31, 2024) | $ 110,000,000.0 |  |  | 105,700,000
The Lemonade Foundation | Affiliated entity |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Contribution to the Lemonade Foundation (in shares) | shares | 500,000 |  | 500,000 |
Contribution of common stock to related party, fair value (usd per share) | $ / shares |  | $ 24.36 |  |
Due from related party (less than for December 31, 2024) | $ 0 |  |  | 100,000
Outstanding amounts due (less than for December 31, 2024) | $ 0 |  |  | $ 100,000
The Lemonade Foundation | Affiliated entity | Lemonade, Inc. |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Shares owned by foundation (in shares) | shares | 400,000 |  |  | 400,000
Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Number of shared directors | director | 2 |  |  |

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