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Related Party Transactions (Details)	3 Months Ended		6 Months Ended		12 Months Ended
Related Party Transactions (Details)	Jun. 30, 2023 USD ($) director	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) director $ / shares shares	Jun. 30, 2022 USD ($)	Dec. 31, 2021 shares	Dec. 31, 2020 shares	Dec. 31, 2022 USD ($)
Related Party Transaction [Line Items]
Due to related party	$ 700,000		$ 700,000				$ 1,100,000
Due from related party	70,300,000		70,300,000				75,200,000
Outstanding amounts due	79,800,000		79,800,000				$ 84,500,000
Follow-on Offering, Selling Shareholders
Related Party Transaction [Line Items]
Common stock sold (in shares) \| shares					1,524,314
Travel related expenses
Related Party Transaction [Line Items]
Related party expenses		$ 100,000	$ 100,000	$ 100,000
Travel related expenses \| Immediate Family Member of Management or Principal Owner
Related Party Transaction [Line Items]
Travel expense	$ 100,000
Related Party
Related Party Transaction [Line Items]
Number of shared directors \| director	2		2
Contribution to the Lemonade Foundation (in shares) \| shares			500,000
Contribution of common stock to related party, fair value (usd per share) \| $ / shares			$ 24.36
Due from related party	$ 0		$ 0
Outstanding amounts due	$ 0		$ 0
Related Party \| Follow-on Offering, Selling Shareholders
Related Party Transaction [Line Items]
Common stock sold (in shares) \| shares						100,000