Lease Commitments - Additional Information (Details)	12 Months Ended
Dec. 31, 2022
Leases [Abstract]
Maximum potential payment increase	5.00%

Operating leases, maximum potential existing payment increase.

No definition available.

Name:	ctg_OperatingLeasesMaximumPotentialExistingPaymentIncrease
Namespace Prefix:	ctg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration