Commitments and Contingencies (Details) - October 2014 Share Repurchase Program - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		9 Months Ended	10 Months Ended
	Oct. 21, 2015	Dec. 31, 2014	Sep. 30, 2015	Sep. 30, 2015	Oct. 22, 2014
Stock Repurchases
Amount authorized under stock repurchase plan					$ 200.0
Share repurchases made in open market (in shares)	616,075	232,170	2,537,081	2,769,251
Average Price Paid per Share (in dollars per share)		$ 60.65	$ 60.98
Aggregate Cost	$ 31.2	$ 14.1	$ 154.7	$ 168.8