Income Taxes - Valuation Allowance (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation Allowance [Line Items]
Valuation Allowance, Deferred Tax Asset, Change in Beginning of the Year Amount		$ (1.6)	$ 735.2	$ 0
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year		873.1	22.3	21.6
Change in valuation allowance	736.0
Balance at end of year		764.1	873.1	22.3
Included in income tax expense (benefit) [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Change in valuation allowance		21.9	865.5	0.7
Change in deferred assets related to other comprehensive income [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Change in valuation allowance		(130.9)	0	0
Included in stockholders' equity related to issuance of exchangeable debt [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Change in valuation allowance		$ 0	$ (14.7)	$ 0