Earnings per Common Share (Details) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Weighted-average shares - basic	416,173	420,986	416,785	420,664
Dilution effect of stock appreciation rights and stock awards at end of period (in shares)	1,920	2,467	1,683	2,160
Weighted-average shares - diluted	418,093	423,453	418,468	422,824
Weighted-average stock awards and shares excluded from diluted earnings per share due to the anti-dilutive effect	0	1	461	3