Subsequent Events (Details)	Feb. 18, 2020 shares
Subsequent Events \| Common Stock
Subsequent Event [Line Items]
Contribution to the Lemonade Foundation (shares)	500,000

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration