Document and Entity Information - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Mar. 27, 2020	Jun. 28, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	NANOPHASE TECHNOLOGIES Corp
Entity Central Index Key	0000883107
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Entity File Number	000-22333
Entity Incorporation, State Code	DE
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filer	No
Entity Reporting Status Current	Yes
Entity Interactive Data Current	Yes
Entity Small Business	true
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth	false
Entity Shell Company	false
Entity Public Float			$ 8,291,014
Entity Common Stock, Shares Outstanding		381,367,92.
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2019