Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2014

Stockholders' Equity Note [Abstract]

Changes To Equity

Shares of our common stock outstanding and activity for the years ended December 31, 2014, 2013 and 2012 are presented below:

	Years Ended December 31,
	2014		2013		2012
Common shares outstanding at January 1	198,830,351		203,551,496		209,332,646
Issuance of restricted stock, excluding restricted stock with performance feature	376,622		292,855		691,207
Vesting of performance units	416,111		210,819		869,231
Vesting of restricted stock with performance feature	77,430		15,141		146,400
Forfeitures of restricted stock	(76,107	)	(15,794	)	(3,975	)
Purchase of treasury stock (1)	(3,538,317	)	(5,224,166	)	(7,484,013	)
Common shares outstanding at December 31	196,086,090		198,830,351		203,551,496

(1) Includes 279,680, 235,922 and 560,484 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, as well as other stock repurchases under separate authority from our Board of Directors.