Employee Benefit Plans, 401(k) plan and Deferred Compensation Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee Benefit Textuals [Abstract]
Employee Contribution Matched in Percent	30.00%
Matching Contributions to Plan	$ 19.6	$ 20.2	$ 20.7
NQDC [Member]
Employee Benefit Textuals [Abstract]
Deferred Compensation Liability	$ 17.7	$ 16.3