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Investment Securities (Fair Value Measurements) (Details) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Maximum percentage of price difference provided by pricing services	5.00%
Maximum price difference provided by pricing services	$ 1.0
Fair value, investment-related liabilities	$ 84.6	$ 86.3

X

- Definition

Fair value of obligations incurred from short sales.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 320

-Section 35

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=29643654&loc=d3e42429-110968

+ Details

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X

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X

- Definition

Represents the maximum price difference provided by the pricing services between the market price and the actual sale price of securities, on the basis of which outliers are considered.

+ References

No definition available.

+ Details

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X

- Definition

Represents the maximum percentage of price difference provided by the pricing services between the market price and the actual sale price of securities, on the basis of which outliers are considered.

+ References

No definition available.

+ Details

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