Cover - USD ($)	12 Months Ended
	Mar. 31, 2022	May 31, 2022	Sep. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Mar. 31, 2022
Current Fiscal Year End Date	--03-31
Document Transition Report	false
Entity File Number	001-08762
Entity Registrant Name	ITERIS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	95-2588496
Entity Address, Address Line One	1250 S. Capital of Texas Hwy., Building 1, Suite 330
Entity Address, City or Town	Austin
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	78746
City Area Code	512
Local Phone Number	716-0808
Title of 12(b) Security	Common Stock, $0.10 par value
Trading Symbol	ITI
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 223,257,646
Entity Common Stock, Shares Outstanding		42,429,597
Documents Incorporated by Reference	Part III of this report incorporates by reference certain information from the registrant's definitive proxy statement for the 2022 Annual Meeting of Stockholders, which will be filed with the Securities and Exchange Commission not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.
Entity Central Index Key	0000350868
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY