Location and Fair Values of Derivative Financial Instruments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivative [Line Items]
Asset Derivatives Fair Value	$ 10.8	$ 81.6
Liability Derivatives Fair Value	135.6	170.5
Designated as Hedging Instrument | Other Long-term Investments
Derivative [Line Items]
Asset Derivatives Fair Value	10.8	81.6
Designated as Hedging Instrument | Other Liability
Derivative [Line Items]
Liability Derivatives Fair Value	133.7	170.5
Designated as Hedging Instrument | Interest Rate Swaps | Other Long-term Investments
Derivative [Line Items]
Asset Derivatives Fair Value	9.2	76.5
Designated as Hedging Instrument | Interest Rate Swaps | Other Liability
Derivative [Line Items]
Liability Derivatives Fair Value	35.0	31.7
Designated as Hedging Instrument | Foreign Exchange Contracts | Other Long-term Investments
Derivative [Line Items]
Asset Derivatives Fair Value	1.6	5.1
Designated as Hedging Instrument | Foreign Exchange Contracts | Other Liability
Derivative [Line Items]
Liability Derivatives Fair Value	98.7	138.8
Not Designated as Hedging Instrument | Other Liability
Derivative [Line Items]
Liability Derivatives Fair Value	55.1
Not Designated as Hedging Instrument | Credit Default Swaps | Other Liability
Derivative [Line Items]
Liability Derivatives Fair Value	1.9
Not Designated as Hedging Instrument | Embedded Derivative in Modified Coinsurance Arrangement | Other Liability
Derivative [Line Items]
Liability Derivatives Fair Value	$ 53.2	$ 83.9