Employee Benefit Plans (Savings Plan) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, 401(k) Savings Plan, Employer Contribution Match of Employees Eligible Compensation	100.00%
Defined Benefit Plan, 401(k) Savings Plan, Maximum Employee Match Percent for Employer Match	5.00%
Defined Benefit, 401(k) Savings Plan Expense	$ 12.5	$ 12.8