Separation Costs and Activities Separation Costs and Acivities - Narrative (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Separation expense		$ 39.4	$ 0.0	$ 0.0
Restricted Stock
Restructuring Cost and Reserve [Line Items]
Granted (in shares)		0.4	0.0	0.1
Restricted Stock | Spinoff
Restructuring Cost and Reserve [Line Items]
Granted (in shares)	0.4
Anniversary period from grant date (in years)	2 years