Geographic and Group Information (Narrative) (Details) - USD ($) $ in Millions	Sep. 27, 2019	Sep. 28, 2018
Segment Reporting [Abstract]
Goodwill included in foreign assets	$ 13.8	$ 14.5
Operating lease ROA included in foreign assets	$ 5.6

Operating lease right of use assets included in foreign assets.

No definition available.

Name:	hckt_OperatingLeaseRightOfUseAssetsIncludedInForeignAssets
Namespace Prefix:	hckt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant