Employee Benefit Plans Deferred Compensation Plan (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Deferred compensation distributions	$ 0.7	$ 1.2	$ 6.1
Deferred compensation arrangement with individuals, recorded liability	5.1	5.6
Increase in deferred compensation liability	$ 0.1	$ 0.3	$ 0.8