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Investment Securities (Other Long-Term Investments) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Hedge funds |  |
Investment securities |  |
Number of Investments Held | 15 |
Trading Securities, Other | $ 120.8 |
Private equity funds |  |
Investment securities |  |
Number of Investments Held | 39 |
Trading Securities, Other | 118.2 |
Total hedge and private equity funds included in other long-term investments |  |
Investment securities |  |
Other Long-term Investments Largest Single Investment | 18.3 | 16.0
Trading Securities, Other | $ 239.0 | $ 239.8

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- Definition Amount of other investments classified as trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),1(c),(d),(e),(f),(g)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph c, d, e, f, g -Article 7 + Details
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