Summary of Gross Revenues and Reimbursements (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 01, 2016	Oct. 02, 2015	Jul. 03, 2015	Apr. 03, 2015	Jan. 02, 2015	Oct. 03, 2014	Jul. 04, 2014	Apr. 04, 2014	Jan. 01, 2016		Jan. 02, 2015		Jan. 03, 2014
Gross Revenues And Reimbursements [Line Items]
Gross revenues									$ 320,404		$ 313,723		$ 302,742
Less: Subcontractor fees									7,572		9,019		6,574
Revenues	$ 73,681	$ 78,994	$ 79,864	$ 80,293	$ 73,611	$ 78,557	$ 76,574	$ 75,962	312,832	[1]	304,704	[1]	296,168	[1]
Reimbursements:
Out-of-pocket reimbursements									5,967		5,862		6,619
Other outside direct expenses									11,160		9,633		9,506
Reimbursements									17,127		15,495		16,125
Revenues before reimbursements	$ 69,789	$ 74,503	$ 75,272	$ 76,141	$ 69,647	$ 74,264	$ 72,331	$ 72,967	$ 295,705		$ 289,209		$ 280,043

[1] Geographic revenues are allocated based on the location of the client.