Nature of the Business	9 Months Ended
Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business	Nature of the BusinessLemonade, Inc. is a public benefit corporation organized under Delaware law on June 17, 2015. It provides certain personnel, facilities and services to each of its subsidiaries (together with Lemonade, Inc., the “Company”), all of which are 100% owned, directly or indirectly, by Lemonade, Inc. For the list of the Company's US and EU subsidiaries, see Note 1 - Nature of the Business, of the audited consolidated financial statements and related notes thereto for the year ended December 31, 2019 as contained in the Company's final prospectus for its initial public offering of its common stock ("IPO") dated as of July 1, 2020 and filed with the SEC pursuant to Rule 424(b)(4) on July 2, 2020.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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