Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 30, 2019
Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	LYFT
Entity Registrant Name	Lyft, Inc.
Entity Central Index Key	0001759509
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Class A Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		277,828,438
Class B Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		12,779,709