Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2012

Stockholders' Equity Note [Abstract]

Summary of Authorized and Issued Shares

Our authorized and issued shares (share amounts stated in whole numbers) consist of the following:

	Par Value		September 30, 2012	December 31, 2011	September 30, 2011
Preferred Stock	$.01	/share
Shares authorized			5,000,000	5,000,000	5,000,000
Shares issued			—	—	—
Common Stock	$.01	/share
Shares authorized			400,000,000	400,000,000	400,000,000
Shares issued			296,307,832	295,258,674	295,203,874

Schedule of Dividends Paid and Declared

The following table presents the dividends either paid previously or declared by our board of directors for future payment:

	2012		2011
First quarter	$	0.17	0.25
Second quarter	$	0.17	0.13
Third quarter	$	0.19	0.13
Fourth quarter	$	0.21	0.14
Total	$	0.74	0.65

Summary of Stock Options Granted

The following tables summarize the details of grants made under our stock option plan of options that have been granted and are outstanding, and the assumptions used to value these options. All options granted were effective at the close of business on the date of grant.

		Option		Closing
		exercise		stock price		September 30, 2012
	Options	(strike)		on date		Options	Options
Date of grant	granted	price		of grant		outstanding	vested
April 17, 2012	1,235,000	$	54.00	$	49.01	1,192,500	—
April 19, 2011	410,000	$	35.00	$	31.78	380,000	—
April 20, 2010	530,000	$	30.00	$	27.13	380,000	—
April 21, 2009	790,000	$	27.00	$	17.61	590,000	—
April 15, 2008	550,000	$	27.00	$	24.35	305,167	135,167
April 17, 2007	4,380,000	$	22.50	$	20.15	2,328,425	1,276,175
Total	7,895,000					5,176,092	1,411,342

Summary of Fair Value Assumptions for Options Granted

Date of grant	Risk-free interest rate		Expected life of option in years	Expected dividend yield		Expected stock volatility		Estimated fair value of stock option
April 17, 2012	0.9	%	5.00	1.4	%	39.25	%	$	13.69
April 19, 2011	2.1	%	5.00	1.6	%	39.33	%	$	11.20
April 20, 2010	2.6	%	5.00	1.5	%	39.10	%	$	8.14
April 21, 2009	1.9	%	5.00	1.0	%	38.80	%	$	3.64
April 15, 2008	2.7	%	5.00	1.0	%	30.93	%	$	7.75
April 17, 2007	4.6	%	4.85	1.0	%	31.59	%	$	5.63

Reconciliation of Denominators used in Computation of Basic and Diluted Earnings Per Share

The following tables present a reconciliation of the denominators used in the computation of basic and diluted earnings per share and a summary of the options to purchase shares of common stock which were excluded from the diluted earnings calculation because they were anti-dilutive:

	Nine-month period		Three-month period
Reconciliation	2012	2011	2012	2011
Basic-weighted average shares outstanding	295,964,359	294,994,553	296,237,956	295,144,175
Weighted shares assumed upon exercise of stock options	1,119,341	768,209	940,790	750,788
Diluted-weighted average shares outstanding	297,083,700	295,762,762	297,178,746	295,894,963

Summary of Anti-Dilutive Options Excluded

	Nine-month period		Three-month period
Summary of anti-dilutive options excluded	2012	2011	2012	2011
Options to purchase shares of common stock	735,675	668,791	1,578,804	818,261
Weighted-average exercise price of options	$54.00	$31.85	$49.43	$32.51