Basis of Presentation and General Information (Carrying Amount And Activity Of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2017	Dec. 30, 2016
Carrying amount and activity of goodwill
Goodwill, Beginning Balance	$ 72,376	$ 74,584
Additions (see Note 14)	11,396
Foreign currency translation adjustment	1,302	(2,208)
Goodwill, Ending Balance	85,074	72,376
The Hackett Group [Member]
Carrying amount and activity of goodwill
Goodwill, Beginning Balance	41,242	43,450
Additions (see Note 14)	1,858
Foreign currency translation adjustment	1,302	(2,208)
Goodwill, Ending Balance	44,402	41,242
Hackett Technology Solutions [Member]
Carrying amount and activity of goodwill
Goodwill, Beginning Balance	31,134	31,134
Additions (see Note 14)	9,538
Goodwill, Ending Balance	$ 40,672	$ 31,134