Share Capital (Tables)

9 Months Ended

Sep. 30, 2012

Stockholders' Equity Note [Abstract]

Changes in share capital

Changes in share capital during the nine months ended September 30, 2012, are as follows:

	Shares		Amount
Balance at December 31, 2011	258,669,487		$	693,899
Common shares issued:
Option exercises	138,334		234
Deferred share units exercised	29,010		39
Unclaimed shares forfeited	(50,869	)	—
Bonus shares and other	165,009		308
Balance at September 30, 2012	258,950,971		$	694,480