Document and Entity Information	3 Months Ended
	Mar. 31, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	Silk Road Medical Inc
Entity Central Index Key	0001397702
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Document Type	S-1
Amendment Flag	false