Stockholders' Equity (Changes To Equity) (Details)	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Increase (Decrease) in Common Shares Outstanding [Roll Forward]
Common shares outstanding at January 1	203,551,496,000		209,332,646,000		106,529,376,000		106,132,538,000
Common shares issued in connection with merger with Frontier	0		103,270,002,000		0
Issuance of common shares upon exercise of stock options	0		0		80,400,000
Issuance of restricted stock, excluding restricted stock with performance feature	691,207,000		512,880,000		282,886,000
Vesting of performance units	869,231,000		233,134,000		140,286,000
Vesting of restricted stock with performance feature	146,400,000		124,332,000		12,300,000
Forfeitures of restricted stock	(3,975,000)		(3,730,000)		(30,084,000)
Purchase of treasury stock	(7,484,013,000)	[1]	(1,333,348,000)	[1]	(88,950,000)	[1]
Common shares outstanding at December 31	203,551,496,000		209,332,646,000		106,529,376,000		106,132,538,000

[1] Includes 560,484, 747,225 and 88,950 shares, respectively, withheld under the terms of stock-based compensation agreements to provide funds for the payment of payroll and income taxes due at the vesting of share-based awards.