Employee Benefit Plans (Contributions to Defined Contribution Plans) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contributions to defined contribution plans	$ 16,100,000	$ 14,800,000	$ 13,700,000
Discontinued Operations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contributions to defined contribution plans	$ 0	$ 0	$ 400,000