Fair Value Measurement (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Fair Value Disclosures [Abstract]
Other Company Stock Owned Fair Value Discount Percentage			5.00%
Carrying value of loans fully charged-off			$ 0
Net gain (loss) representing the change in fair value in earnings	$ 5.7	$ 5.3	$ 11.1	$ 11.3

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 30

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

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