Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 30, 2020
Document And Entity Information [Abstract]
Document Type	10-Q
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Registrant Name	ATEL 17, LLC
Entity Central Index Key	0001640982
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Smaller Reporting Company	true
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Units Outstanding		2,565,749