Employee Benefit Plans (Defined Contribution Plan) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Employee Savings Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer contributions	$ 7.1	$ 7.6	$ 6.9