Number Of Shared Directors

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- Definition

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

+ References

No definition available.

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- Definition

Stock Issued During Period, Shares, Issued for Charitable Contribution

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- Definition

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Noncash charitable contributions made by the entity during the period.

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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Related Party Transactions (Details) $ / shares in Units, $ in Millions			3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 14, 2021 shares	Feb. 18, 2020 shares	Sep. 30, 2021 USD ($) director	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) director $ / shares shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) director $ / shares shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Related Party Transaction [Line Items]
Outstanding amounts from related parties			$ 0.0		$ 0.0		$ 0.0
Outstanding amounts to related parties			0.0		0.0		0.0
Common shares contribution to the Lemonade Foundation					0.0	$ 12.2	12.2	$ 0.0	$ 0.0
Follow On Offering, Selling Shareholders
Related Party Transaction [Line Items]
Common stock sold (shares) \| shares	1,524,314
The Lemonade Foundation
Related Party Transaction [Line Items]
Outstanding amounts from related parties			0.0		0.0
Outstanding amounts to related parties			0.0		0.0
The Lemonade Foundation \| Follow On Offering, Selling Shareholders
Related Party Transaction [Line Items]
Common stock sold (shares) \| shares	100,000
Key stockholder \| Travel related expenses
Related Party Transaction [Line Items]
Expenses with related parties			$ 0.1	$ 0.1	$ 0.1	0.1	$ 0.1	0.3	0.2
Affiliated entity \| The Lemonade Foundation
Related Party Transaction [Line Items]
Number of shared directors \| director			2		2		2
Contribution to the Lemonade Foundation (shares) \| shares		500,000			500,000		500,000
Contribution of common stock to related party, fair value (usd per share) \| $ / shares					$ 24.36		$ 24.36
Common shares contribution to the Lemonade Foundation							$ 12.2
Affiliated entity \| Rental expense
Related Party Transaction [Line Items]
Expenses with related parties			$ 0.1	$ 0.1	$ 0.1	$ 0.1	$ 0.1	$ 0.1	$ 0.1