CONVERTIBLE SENIOR NOTES - Minimum interest payments (Details) - Convertible Senior Notes $ in Thousands	Sep. 30, 2023 USD ($)
Minimum interest payments
October 1, 2023 through December 31, 2023	$ 1,592
2024	3,050
2025	3,042
2026	$ 1,508

Amount of interest on long-term debt payable issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year.

No definition available.

Name:	zyxi_LongTermDebtMaturitiesRepaymentsOfInterestYearThree
Namespace Prefix:	zyxi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant