Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2022	Jul. 25, 2022
Cover [Abstract]
Entity Registrant Name	DZS INC
Entity Central Index Key	0001101680
Trading Symbol	DZSI
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		27,893,797
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	000-32743
Entity Tax Identification Number	22-3509099
Entity Address, Address Line1	5700 Tennyson Parkway, Suite 400
Entity Address, City or Town	Plano
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75024
City Area Code	469
Local Phone Number	327-1531
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Entity Interactive Data Current	Yes
Title of each class	Common stock, $0.001 par value
Name of each exchange on which registered	NASDAQ