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Investment Securities (Details 5) (USD $) In Millions, unless otherwise specified | Jun. 30, 2011 | Dec. 31, 2010
--- | --- | ---
Hedge and private equity funds included in other long-term investments |  |
Other long-term investments |  |
Largest single fund investment | $ 34.3 |
Other long-term investments | 283.5 | 315.5
Unfunded Commitments | 83.8 | 88.7
Hedge funds |  |
Other long-term investments |  |
Number of limited partnership and limited liability corporation investments | 17 |
Other long-term investments | 139.1 | 155.7
Distributions outstanding | 3.6 |
Redemption requests | 2.2 |
Hedge funds | Monthly |  |
Other long-term investments |  |
Other long-term investments | 5.7 |
Hedge funds | Monthly | 120+ days notice |  |
Other long-term investments |  |
Other long-term investments | 5.7 |
Hedge funds | Quarterly |  |
Other long-term investments |  |
Other long-term investments | 80.7 |
Hedge funds | Quarterly | 30-59 days notice |  |
Other long-term investments |  |
Other long-term investments | 27.7 |
Hedge funds | Quarterly | 60-89 days notice |  |
Other long-term investments |  |
Other long-term investments | 32.9 |
Hedge funds | Quarterly | 90-119 days notice |  |
Other long-term investments |  |
Other long-term investments | 20.1 |
Hedge funds | Semi-annual |  |
Other long-term investments |  |
Other long-term investments | 20.4 |
Hedge funds | Semi-annual | 60-89 days notice |  |
Other long-term investments |  |
Other long-term investments | 5.5 |
Hedge funds | Semi-annual | 120+ days notice |  |
Other long-term investments |  |
Other long-term investments | 14.9 |
Hedge funds | Annual |  |
Other long-term investments |  |
Other long-term investments | 32.3 |
Hedge funds | Annual | 30-59 days notice |  |
Other long-term investments |  |
Other long-term investments | 23.7 |
Hedge funds | Annual | 90-119 days notice |  |
Other long-term investments |  |
Other long-term investments | 7.7 |
Hedge funds | Annual | 120+ days notice |  |
Other long-term investments |  |
Other long-term investments | 0.9 |
Hedge funds | 30-59 days notice |  |
Other long-term investments |  |
Other long-term investments | 51.4 |
Hedge funds | 60-89 days notice |  |
Other long-term investments |  |
Other long-term investments | 38.4 |
Hedge funds | 90-119 days notice |  |
Other long-term investments |  |
Other long-term investments | 27.8 |
Hedge funds | 120+ days notice |  |
Other long-term investments |  |
Other long-term investments | 21.5 |
Long/short equity |  |
Other long-term investments |  |
Other long-term investments | 51.1 | 50.4
Long/short credit & distressed |  |
Other long-term investments |  |
Other long-term investments | 35.3 | 34.1
Long diversified strategies |  |
Other long-term investments |  |
Other long-term investments | 23.8 | 24.0
Long/short equity REIT |  |
Other long-term investments |  |
Other long-term investments | 14.9 | 25.2
Long/short equity activist |  |
Other long-term investments |  |
Other long-term investments | 13.1 | 16.9
Long bank loan |  |
Other long-term investments |  |
Other long-term investments | 0.9 | 5.1
Private equity funds |  |
Other long-term investments |  |
Number of limited partnership and limited liability corporation investments | 33 |
Other long-term investments | 144.4 | 159.8
Unfunded Commitments | 83.8 | 88.7
Private equity funds | 1-3 years |  |
Other long-term investments |  |
Other long-term investments | 50.8 |
Private equity funds | 5-10 years |  |
Other long-term investments |  |
Other long-term investments | 79.5 |
Private equity funds | >10 years |  |
Other long-term investments |  |
Other long-term investments | 14.1 |
Distressed residential real estate |  |
Other long-term investments |  |
Other long-term investments | 34.3 | 49.2
Energy infrastructure and services |  |
Other long-term investments |  |
Other long-term investments | 27.5 | 24.2
Unfunded Commitments | 9.9 | 10.8
Multi-sector |  |
Other long-term investments |  |
Other long-term investments | 26.8 | 26.0
Unfunded Commitments | 9.1 | 10.6
Manufacturing/Industrial |  |
Other long-term investments |  |
Other long-term investments | 14.1 | 17.9
Private equity secondaries |  |
Other long-term investments |  |
Other long-term investments | 11.2 | 10.4
Unfunded Commitments | 4.0 | 4.4
Real estate |  |
Other long-term investments |  |
Other long-term investments | 9.8 | 9.1
Unfunded Commitments | 4.2 | 4.6
International multi-sector, Europe |  |
Other long-term investments |  |
Other long-term investments | 8.3 | 10.5
Unfunded Commitments | 5.1 | 5.3
International multi-sector, Asia |  |
Other long-term investments |  |
Other long-term investments | 3.8 | 4.9
Unfunded Commitments | 2.7 | 2.7
Insurance |  |
Other long-term investments |  |
Other long-term investments | 3.6 | 3.9
Unfunded Commitments | 41.3 | 41.3
Venture capital fund |  |
Other long-term investments |  |
Other long-term investments | 2.6 | 2.2
Unfunded Commitments | 0.5 | 1.0
Healthcare |  |
Other long-term investments |  |
Other long-term investments | 2.4 | 1.5
Unfunded Commitments | $ 7.0 | $ 8.0

X
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