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Investment Securities (Fair Value of Hedge Funds Subject to Restrictions on Redemption Frequency) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
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Private equity funds |  |
Investment securities |  |
Trading Securities, Other | $ 118.2 |
Hedge funds |  |
Investment securities |  |
Trading Securities, Other | 120.8 |
Total hedge and private equity funds included in other long-term investments |  |
Investment securities |  |
Trading Securities, Other | 239.0 | 239.8
Fair value unfunded commitments | 110.6 | 119.4
Other Long-term Investments Largest Single Investment | 18.3 | 16.0
Private equity funds | Private equity funds |  |
Investment securities |  |
Trading Securities, Other | 118.2 | 125.2
Fair value unfunded commitments | 110.6 | 119.4
Private equity funds | Multi-sector |  |
Investment securities |  |
Trading Securities, Other | 23.8 | 23.3
Fair value unfunded commitments | 6.5 | 5.4
Private equity funds | Energy infrastructure & services |  |
Investment securities |  |
Trading Securities, Other | 45.9 | 36.3
Fair value unfunded commitments | 13.1 | 15.6
Private equity funds | Distressed residential real estate |  |
Investment securities |  |
Trading Securities, Other | 0.4 | 15.8
Fair value unfunded commitments | 0 | 0
Private equity funds | Real estate |  |
Investment securities |  |
Trading Securities, Other | 8.2 | 11.6
Fair value unfunded commitments | 3.3 | 3.3
Private equity funds | Private equity secondaries |  |
Investment securities |  |
Trading Securities, Other | 9.5 | 10.5
Fair value unfunded commitments | 3.1 | 3.1
Private equity funds | International multi-sector, Europe |  |
Investment securities |  |
Trading Securities, Other | 3.9 | 5.1
Fair value unfunded commitments | 2.8 | 5.0
Private equity funds | Manufacturing/Industrial |  |
Investment securities |  |
Trading Securities, Other | 11.2 | 9.9
Fair value unfunded commitments | 15.5 | 15.1
Private equity funds | Healthcare |  |
Investment securities |  |
Trading Securities, Other | 5.6 | 4.3
Fair value unfunded commitments | 2.8 | 5.4
Private equity funds | International multi-sector, Asia |  |
Investment securities |  |
Trading Securities, Other | 0 | 0.4
Fair value unfunded commitments | 2.7 | 2.7
Private equity funds | Insurance |  |
Investment securities |  |
Trading Securities, Other | 2.3 | 3.0
Fair value unfunded commitments | 41.3 | 41.3
Private equity funds | Aerospace/Defense/Government |  |
Investment securities |  |
Trading Securities, Other | 5.8 | 2.8
Fair value unfunded commitments | 19.2 | 22.2
Private equity funds | Venture capital |  |
Investment securities |  |
Trading Securities, Other | 1.6 | 2.2
Fair value unfunded commitments | 0.3 | 0.3
Hedge funds | Hedge funds |  |
Investment securities |  |
Trading Securities, Other | 120.8 | 114.6
Fair value unfunded commitments | 0 | 0
Hedge funds | Long/short equity |  |
Investment securities |  |
Trading Securities, Other | 62.6 | 60.3
Fair value unfunded commitments | 0 | 0
Hedge funds | Long/short credit & distressed |  |
Investment securities |  |
Trading Securities, Other | 22.8 | 22.7
Fair value unfunded commitments | 0 | 0
Hedge funds | Long diversified strategies |  |
Investment securities |  |
Trading Securities, Other | 0.1 | 1.7
Fair value unfunded commitments | 0 | 0
Hedge funds | Long/short equity REIT |  |
Investment securities |  |
Trading Securities, Other | 18.3 | 16.0
Fair value unfunded commitments | 0 | 0
Hedge funds | Long/short equity activist |  |
Investment securities |  |
Trading Securities, Other | 16.8 | 13.6
Fair value unfunded commitments | 0 | 0
Hedge funds | Long bank loan |  |
Investment securities |  |
Trading Securities, Other | 0.2 | 0.3
Fair value unfunded commitments | $ 0 | $ 0

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- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=SL6742756-110258 + Details
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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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