Convertible Perpetual Preferred Stock - Table 1 (Details) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Temporary Equity [Abstract]
Temporary Equity, Carrying Amount, Attributable to Parent, Ending		$ 93.2	$ 93.2	$ 342.2
Convertible Preferred Stock [Member]
Temporary Equity [Abstract]
Temporary Equity, Shares Outstanding, Beginning Balance			353,355	400,000
Temporary Equity, Repurchased during Period, Shares	(257,110)	(257,110)	(257,110)	(46,645)
Temporary Equity, Shares Outstanding, Ending Balance		96,245	96,245	353,355
Temporary Equity, Carrying Amount, Attributable to Parent, Beginning			342.2	387.4
Temporary Equity, Carrying Amount, Period Increase (Decrease)			(249.0)	(45.2)
Temporary Equity, Carrying Amount, Attributable to Parent, Ending		$ 93.2	$ 93.2	$ 342.2