Employee Benefit Plan (Narrative) (Details) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended			0 Months Ended
	Jan. 02, 2012	Jan. 31, 2008	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jan. 02, 2013 Employee Benefit Plan [Member]
Employee Benefit Plan [Abstract]
Employee benefit plan			$ 6,400,000	$ 3,400,000	$ 2,600,000
Percentage of company match that vests annually			25.00%
Subsequent Event [Line Items]
Employee benefit plan, amended matching contribution	1/2	1/2				1/2
Percentage of employee contribution matched by the company	8.00%	8.00%				8.00%
Maximum amount that company will match annually per employee (whole number)	$ 4,000,000			$ 2,000	$ 2,000	$ 6,000