Capital Stock (Tables)

9 Months Ended

Sep. 30, 2011

Capital Stock [Abstract]

Capital Stock

	Nine Months		Year
	Ended		Ended
	September 30,		December 31,
	2011		2010
Beginning balance		159,909,052		158,118,937
Stock options/SARs exercised		693,326		991,988
Restricted stock grants		326,591		405,127
Treasury shares issued		29,841		12,771
Shares issued for acreage purchases		—		380,229
Ending balance		160,958,810		159,909,052