Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 29, 2020	Jun. 28, 2019
Document And Entity Information [Abstract]
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
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 Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	No
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Public Float			$ 0
Entity Units Outstanding		2,565,749