Stock-Based Compensation Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of options granted		550,812		8,173,944		2,252,457
Weighted Average Grant-Date Fair Value per share		$ 5.95	[1]	$ 3.50	[1]	$ 10.55	[1]
Weighted Average Exercise Price per Share		$ 13.65	[1]	$ 8.44	[1],[2]	$ 26.23	[1],[2]
Number of options exercised		143,109		0		0
Cash received for options exercised		$ 1.2		$ 0		$ 0
Intrinsic value of options exercised		1.5		0		0
Intrinsic Value of Options Vested and Expected to Vest		$ 86.1		$ 0		$ 0
Stock split ratio	1.742

[1] Represents the weighted-average grant date fair value per option, using the Monte Carlo simulation option-pricing model for performance-based options, and the Black-Scholes option-pricing model for time-based options.

[2] Adjusted for the February 2012 1.742-for-1 stock split.