v2.4.0.6

Common shares (Details) In Millions, except Share data, unless otherwise specified | 0 Months Ended | 1 Months Ended
--- | --- | ---
Aug. 17, 2012 | Aug. 08, 2012 CAD item | Jul. 31, 2012 USD ($) | Jul. 31, 2012 CAD | Nov. 30, 2011 | Oct. 31, 2011 USD ($) | Oct. 31, 2011 CAD | Oct. 31, 2010 USD ($)
Common shares |  |  |  |  |  |  |  |
Shares issued in connection with acquisition |  |  |  |  | 31,500,215 |  |  |
Issuance of common shares |  |  | 5,567,177 | 5,567,177 |  | 12,650,000 | 12,650,000 | 6,029,000
Issuance of common shares pursuant to the exercise of underwriters' over-allotment option in public offering |  |  |  |  |  | 1,650,000 | 1,650,000 | 784,000
Price of common shares issued (in dollars per share) |  |  | $ 12.76 | 13.10 |  | $ 13.00 | 13.26 | $ 13.35
Proceed from issuance of common stock public offering net of underwriting discounts and costs |  |  | $ 68.5 |  |  | $ 155.4 |  | $ 75.3
Maximum amount of securities that may be offered and sold |  | 750 |  |  |  |  |  |
Minimum number of series for convertible securities |  | 1 |  |  |  |  |  |
Life of registration statement | 25 months | 3 years |  |  |  |  |  |

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