Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Feb. 18, 2019	Jun. 29, 2018
Document Information [Line Items]
Entity Registrant Name	US XPRESS ENTERPRISES INC
Entity Central Index Key	0000923571
Trading Symbol	usx
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Public Float			$ 484.9
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Shell Company	false
Common Class A [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		32,859,291
Common Class B [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		15,486,560