Capital Stock (Tables)

6 Months Ended

Jun. 30, 2011

Capital Stock [Abstract]

Capital Stock

	Six Months		Year
	Ended		Ended
	June 30,		December 31,
	2011		2010
Beginning balance		159,909,052		158,118,937
Stock options/SARs exercised		558,161		991,988
Restricted stock grants		326,591		405,127
Treasury shares issued		28,903		12,771
Shares issued for acreage purchases		—		380,229
Ending balance		160,822,707		159,909,052