Summary of Gross Revenues and Reimbursements (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 02, 2015	Oct. 03, 2014	Jul. 04, 2014	Apr. 04, 2014	Jan. 03, 2014	Sep. 27, 2013	Jun. 28, 2013	Mar. 29, 2013	Jan. 02, 2015		Jan. 03, 2014		Dec. 28, 2012
Gross Revenues And Reimbursements [Line Items]
Gross revenues									$ 313,723		$ 302,742		$ 298,818
Less: Subcontractor fees									9,019		6,574		6,165
Revenues	73,611	78,557	76,574	75,962	72,772	75,231	75,505	72,660	304,704	[1]	296,168	[1]	292,653	[1]
Reimbursements:
Out-of-pocket reimbursements									5,862		6,619		6,426
Other outside direct expenses									9,633		9,506		19,665
Reimbursements									15,495		16,125		26,091
Revenues before reimbursements	$ 69,647	$ 74,264	$ 72,331	$ 72,967	$ 69,036	$ 70,096	$ 71,919	$ 68,992	$ 289,209		$ 280,043		$ 266,562

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