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Derivatives Derivatives (Forward Contracts Collateral) (Details) In Millions, unless otherwise specified	Dec. 31, 2013 USD ($)	Dec. 31, 2013 JPY (¥)	Dec. 31, 2013 Forward contracts USD ($)		Dec. 31, 2013 Forward contracts SEK	Dec. 31, 2012 Forward contracts USD ($)	Dec. 31, 2013 Barclays [Member] A Forward contracts USD ($)		Dec. 31, 2012 Barclays [Member] A Forward contracts USD ($)	Dec. 31, 2013 Deutsche Bank [Member] A Forward contracts USD ($)		Dec. 31, 2012 Deutsche Bank [Member] A Forward contracts USD ($)	Dec. 31, 2013 Goldman Sachs [Member] Standard & Poor's, A- Rating [Member] Forward contracts USD ($)		Dec. 31, 2012 Goldman Sachs [Member] Standard & Poor's, A- Rating [Member] Forward contracts USD ($)	Dec. 31, 2013 HSBC Bank plc [Member] Standard & Poor's, AA- Rating [Member] Forward contracts USD ($)		Dec. 31, 2012 HSBC Bank plc [Member] Standard & Poor's, AA- Rating [Member] Forward contracts USD ($)	Dec. 31, 2013 J P Morgan Chase [Member] Standard & Poor's, A+ Rating [Member] Forward contracts USD ($)		Dec. 31, 2012 J P Morgan Chase [Member] Standard & Poor's, A+ Rating [Member] Forward contracts USD ($)	Dec. 31, 2013 Royal Bank of Canada [Member] Standard & Poor's, AA- Rating [Member] Forward contracts USD ($)		Dec. 31, 2012 Royal Bank of Canada [Member] Standard & Poor's, AA- Rating [Member] Forward contracts USD ($)
Derivative [Line Items]
Notional amount	$ 1,900.0	¥ 203,600.0	$ 20.4		131.3	$ 31.2	$ 5.8		$ 7.7	$ 7.7		$ 11.1	$ 2.1		$ 0.4	$ 3.3		$ 10.1	$ 1.3		$ 1.9	$ 0.2		$ 0
Uncollaterailized Balance of Forward Currency Derivatives			$ (0.1)	[1]		$ (0.1)	$ 0	[1]	$ (0.1)	$ 0	[1]	$ 0	$ 0	[1]	$ 0	$ (0.1)	[1]	$ 0	$ 0	[1]	$ 0	$ 0	[1]	$ 0
[1] Standard & Poor’s (“S&P”) ratings as detailed above are: “AA-” (Very Strong, which is the sixth highest of twenty-one creditworthiness ratings), “A+” (Strong, which is the seventh highest of twenty-one creditworthiness ratings) and “A” (Strong, which is the eighth highest of twenty-one creditworthiness ratings).

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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- Details

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- Definition

Uncollaterailized Balance of Forward Currency Derivatives

+ References

No definition available.

+ Details

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