Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2015

Stockholders' Equity Note [Abstract]

Authorized, Issued, and Outstanding Shares

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

	Par Value		June 30, 2015	December 31, 2014	June 30, 2014
Preferred stock	$.01	/share
Shares authorized			5,000,000	5,000,000	5,000,000
Shares issued and outstanding			—	—	—
Common stock	$.01	/share
Shares authorized			400,000,000	400,000,000	400,000,000
Shares issued and outstanding			290,149,384	295,867,844	296,764,444

Schedule of Dividends Paid Previously or Declared

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

	2015		2014
First quarter	$	0.28	0.25
Second quarter	0.28		0.25
Third quarter	0.28		0.25
Fourth quarter			0.25
Total	$	0.84	1.00

Stock Options Granted

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

	Options Granted	Option Exercise (Strike) Price		Closing Stock Price on Date of Grant		June 30, 2015
Date of Grant						Options Outstanding	Options Exercisable
April 21, 2015	893,220	$	42.00	$	41.26	880,842	—
April 22, 2014	955,000	$	56.00	$	50.53	807,500	5,000
April 16, 2013	205,000	$	54.00	$	49.25	137,500	—
April 17, 2012	1,235,000	$	54.00	$	49.01	1,060,000	243,750
April 19, 2011	410,000	$	35.00	$	31.78	268,800	143,800
April 20, 2010	530,000	$	30.00	$	27.13	226,500	129,000
April 21, 2009	790,000	$	27.00	$	17.61	303,900	211,400
April 15, 2008	550,000	$	27.00	$	24.35	161,000	134,750
April 17, 2007	4,380,000	$	22.50	$	20.15	1,346,840	1,346,840
Total	9,948,220					5,192,882	2,214,540

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 21, 2015	1.3	%	5.00	2.7	%	26.84	%	$	7.35
April 22, 2014	1.8	%	5.00	2.0	%	28.55	%	$	9.57
April 16, 2013	0.7	%	5.00	1.6	%	37.42	%	$	12.66
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:

	Six-month Period		Three-month Period
Reconciliation	2015	2014	2015	2014
Basic weighted average shares outstanding	293,191,566	296,666,992	291,176,985	296,691,232
Weighted shares assumed upon exercise of stock options	678,586	867,481	653,152	887,187
Diluted weighted average shares outstanding	293,870,152	297,534,473	291,830,137	297,578,419

Anti-Dilutive Options Excluded

	Six-month Period				Three-month Period
Summary of Anti-dilutive Options Excluded	2015		2014		2015		2014
Options to purchase shares of common stock	2,395,247		1,646,892		2,724,639		1,997,363
Weighted average exercise prices of options	$	52.97	$	54.44	$	51.56	$	54.72