Summary of Significant Accounting Policies (Details 6) (USD $)	12 Months Ended
Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Roll forward of the accounts receivable allowance
Balance at beginning of period	$ 7,210,000
Balance at end of period	4,177,000	7,210,000
Foreign Currency Translation
Transaction gains and losses recorded in income (loss) before (provision) benefit for income taxes	300,000	200,000	200,000
Billed Revenues
Roll forward of the accounts receivable allowance
Balance at beginning of period	7,210,000	9,459,000	6,548,000
Increases to reserve	948,000	5,619,000	6,854,000
Amounts written off	(3,993,000)	(7,891,000)	(3,897,000)
Effects of foreign currency translation	30,000	25,000	(46,000)
Balance at end of period	4,177,000	7,210,000	9,459,000
Unbilled Revenues
Roll forward of the accounts receivable allowance
Balance at beginning of period	1,827,000	2,921,000	2,521,000
Increases to reserve	5,242,000	443,000	1,329,000
Amounts written off	(4,836,000)	(1,538,000)	(928,000)
Effects of foreign currency translation		1,000	(1,000)
Balance at end of period	2,233,000	1,827,000	2,921,000
NeuCo, Inc. \| Billed Revenues
Roll forward of the accounts receivable allowance
Change related to NeuCo	$ (18,000)	$ (2,000)

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