Document and Entity Information - $ / shares
9 Months Ended
Sep. 30, 2019
Nov. 29, 2019
Document and Entity Information [Abstract]    
Entity Central Index Key 0001551306  
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Sep. 30, 2019  
Document Transition Report false  
Entity File Number 001-39100  
Entity Registrant Name Progyny, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 27-2220139  
Entity Address, Address Line One 245 5th Avenue  
Entity Address, City or Town New York  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10016  
City Area Code 212  
Local Phone Number 888-3124  
Title of 12(b) Security Common Stock,$0.0001 par value per share  
Trading Symbol PGNY  
Security Exchange Name NASDAQ  
Entity Current Reporting Status No  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   84,046,372
Entity Listing, Par Value Per Share $ 0.0001  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Amendment Flag false