Summary of Significant Accounting Policies (Vertical Market) (Details)	3 Months Ended
	Mar. 29, 2013	Mar. 30, 2012
Revenue by vertical market as a percentage of total revenue
Total revenue	100.00%	100.00%
Healthcare [Member]
Revenue by vertical market as a percentage of total revenue
Total revenue	31.80%	31.50%
Technology service providers [Member]
Revenue by vertical market as a percentage of total revenue
Total revenue	30.40%	31.80%
Financial services [Member]
Revenue by vertical market as a percentage of total revenue
Total revenue	6.60%	6.20%
Energy [Member]
Revenue by vertical market as a percentage of total revenue
Total revenue	6.00%	6.20%
General markets [Member]
Revenue by vertical market as a percentage of total revenue
Total revenue	25.20%	24.30%