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Stock Issued During Period, Issued For Charitable Contribution, Fair Value

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Noncash charitable contributions made by the entity during the period.

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Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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Related Party Transactions (Details)		12 Months Ended
Related Party Transactions (Details)	Feb. 18, 2020 shares	Dec. 31, 2020 USD ($) director $ / shares shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Related Party Transaction [Line Items]
Due to (from) related parties		$ 0	$ 0
Common shares contribution to Lemonade Foundation		$ 12,200,000	0	$ 0
Common Stock
Related Party Transaction [Line Items]
Contribution to the Lemonade Foundation (shares) \| shares		500,000
Key stockholder \| Travel related expenses
Related Party Transaction [Line Items]
Expenses with related parties		$ 100,000	300,000	200,000
Affiliated entity \| The Lemonade Foundation
Related Party Transaction [Line Items]
Number of shared directors \| director		2
Contribution to the Lemonade Foundation (shares) \| shares	500,000	500,000
Contribution of common stock to related party, fair value (usd per share) \| $ / shares		$ 24.36
Common shares contribution to Lemonade Foundation		$ 12,200,000
Due from related party		100,000
Affiliated entity \| Rental expense
Related Party Transaction [Line Items]
Expenses with related parties		$ 100,000	$ 100,000	$ 100,000