Stock-Based Compensation (Subsequent Events) (Details)	Oct. 31, 2020 USD ($)
Scenario, Forecast
Subsequent Event [Line Items]
Total unrecognized stock-based compensation, net of estimated forfeitures and assuming achievement of the pre-established performance goal at a target level, related to stock-based awards authorized for issuance.	$ 6,140,000

Total unrecognized stock-based compensation, net of estimated forfeitures and assuming achievement of the pre-established performance goal at a target level, related to stock-based awards authorized for issuance.

No definition available.

Name:	cmtl_TotalUnrecognizedStockBasedCompensationNetRelatedToStockBasedAwardsAuthorizedForIssuance
Namespace Prefix:	cmtl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant