Summary of Significant Accounting Policies - Summary of IT Solutions and IT and Other Staffing Revenue as Percentage of Total Revenue (Details) - Product Concentration Risk [Member] - Sales Revenue, Services, Net [Member]	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jul. 01, 2016	Jun. 30, 2017	Jul. 01, 2016
Product Information [Line Items]
Revenue, percent	100.00%	100.00%	100.00%	100.00%
IT Solutions [Member]
Product Information [Line Items]
Revenue, percent	29.80%	29.50%	29.90%	29.80%
IT and Other Staffing [Member]
Product Information [Line Items]
Revenue, percent	70.20%	70.50%	70.10%	70.20%