Shareholders' Equity (Tables)

12 Months Ended

Dec. 31, 2011

Shareholders' Equity [Abstract]

Rollforward Of Changes In Common Shares Issued And Outstanding

	Years Ended December 31
	2011			2010			2009
Shares issued, beginning of year		341,094,559			337,841,616			335,413,501
Shares issued, net		–			2,268,000			2,000,000
Exercise of stock options		1,737,853			984,943			168,720
Shares issued under ESPP		–			–			259,395
Shares issued, end of year		342,832,412			341,094,559			337,841,616
Common Shares in treasury, end of year		(5,905,136	)		(6,151,707	)		(1,316,959	)
Shares issued and outstanding, end of year		336,927,276			334,942,852			336,524,657
Common Shares issued to employee trust
Balance, beginning of year		(101,481	)		(101,481	)		(108,981	)
Shares redeemed		92,014			–			7,500
Balance, end of year		(9,467	)		(101,481	)		(101,481	)