Summary of Significant Accounting Policies Vertical Market (Details)	3 Months Ended		6 Months Ended
	Jun. 28, 2013	Jun. 29, 2012	Jun. 28, 2013	Jun. 29, 2012
Segment/Market Reporting Information [Line Items]
Total revenue	100.00%	100.00%	100.00%	100.00%
Healthcare [Member]
Segment/Market Reporting Information [Line Items]
Total revenue	32.00%	33.00%	32.00%	32.00%
Technology Service Providers [Member]
Segment/Market Reporting Information [Line Items]
Total revenue	31.00%	31.00%	30.00%	31.00%
Financial Services [Member]
Segment/Market Reporting Information [Line Items]
Total revenue	6.00%	6.00%	6.00%	6.00%
Energy [Member]
Segment/Market Reporting Information [Line Items]
Total revenue	6.00%	6.00%	6.00%	6.00%
General Markets [Member]
Segment/Market Reporting Information [Line Items]
Total revenue	25.00%	24.00%	26.00%	25.00%