Equity, Cash Dividends on Shares of Common Stock (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended		6 Months Ended
	Jun. 23, 2015	Apr. 23, 2015	Jan. 27, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Stockholders' Equity Note [Abstract]
Cash dividends declared per common stock (in dollar per share)		$ 0.1	$ 0.1	$ 0.1	$ 0	$ 0.2	$ 0
Common stock dividends paid	$ 38.8					$ 79.5