Document and Entity Information
Aug. 07, 2019
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Aug. 07, 2019
Entity Registrant Name KINSALE CAPITAL GROUP, INC.
Entity Incorporation, State or Country Code DE
Entity File Number 001-37848
Entity Tax Identification Number 98-0664337
Entity Address, Address Line One 2221 Edward Holland Drive
Entity Address, Address Line Two Suite 600
Entity Address, City or Town Richmond
Entity Address, State or Province VA
Entity Address, Postal Zip Code 23230
City Area Code 804
Local Phone Number 289-1300
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Entity Central Index Key 0001669162
Title of 12(b) Security Common Stock, par value $0.01
Trading Symbol KNSL
Security Exchange Name NASDAQ