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Significant Transactions (Details 3) (USD $) In Millions, except Share data, unless otherwise specified | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2012 | Mar. 31, 2011 | Dec. 31, 2010 | Nov. 17, 2006 | Dec. 30, 2011 Old Lyme
Business acquisition |  |  |  |  |
Cash to be paid on acquisition |  |  |  |  | $ 6.0
Purchase note acquired |  |  |  |  | 2.1
Share Repurchase |  |  |  |  |
Authorized repurchase of common shares |  |  |  | 1,000,000 |
Additional authorized repurchase of common shares |  |  | 600,000 |  |
Common shares repurchased and retired during the period | 157,629 | 246,284 |  |  |
Value of common shares repurchased and retired during the period | $ 76.0 | $ 86.0 |  |  |
Shares remaining under share repurchase authorization | 30,668 |  |  |  |

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