Shareholders Equity (Rollforward Of Changes In Common Shares Issued And Outstanding) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Shareholders' Equity [Abstract]
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
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)