Derivative Financial Instruments (Details 7) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Effect of derivatives not designated as hedging instruments on the consolidated statements of operations
Amount of gain (loss) recognized in net income on derivatives	$ (51.4)	$ (25.3)	$ (41.1)	$ (78.8)
Interest rate contracts
Effect of derivatives not designated as hedging instruments on the consolidated statements of operations
Amount of gain (loss) recognized in net income on derivatives	38.3	(20.0)	134.7	(112.1)
Foreign exchange contracts
Effect of derivatives not designated as hedging instruments on the consolidated statements of operations
Amount of gain (loss) recognized in net income on derivatives	(43.7)	14.9	(56.6)	3.1
Equity contracts
Effect of derivatives not designated as hedging instruments on the consolidated statements of operations
Amount of gain (loss) recognized in net income on derivatives	37.7	(49.0)	0.1	(120.5)
Credit contracts
Effect of derivatives not designated as hedging instruments on the consolidated statements of operations
Amount of gain (loss) recognized in net income on derivatives	(21.7)	10.4	(10.8)	32.8
Other contracts
Effect of derivatives not designated as hedging instruments on the consolidated statements of operations
Amount of gain (loss) recognized in net income on derivatives	$ (62.0)	$ 18.4	$ (108.5)	$ 117.9