Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2019

Stockholders' Equity Note [Abstract]

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:

	2019		2018
First quarter	$	0.215	0.185
Second quarter	0.215		0.185
Third quarter	0.220		0.200
Fourth quarter	0.220		0.200
Total	$	0.870	0.770

Stock Options Granted

The following tables summarize the details of options granted under our stock option plans that were still outstanding as of September 30, 2019, and the assumptions used to value these grants. All such grants 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		September 30, 2019
Date of Grant						Options Outstanding	Options Exercisable
January 2, 2019	1,316,924	$	26.00	$	25.705	1,292,720	29,010
January 2, 2018	1,087,936	$	27.50	$	27.270	1,027,436	42,370
January 3, 2017	1,529,578	$	23.50	$	23.475	1,231,114	359,900
April 19, 2016	1,690,880	$	23.00	$	22.870	1,261,154	312,714
April 21, 2015	1,786,440	$	21.00	$	20.630	933,636	428,460
April 22, 2014	1,910,000	$	28.00	$	25.265	711,150	465,540
April 16, 2013	410,000	$	27.00	$	24.625	115,346	74,096
April 17, 2012	2,470,000	$	27.00	$	24.505	864,378	757,576
April 19, 2011	820,000	$	17.50	$	15.890	23,500	23,500
Total	13,021,758					7,460,434	2,493,166

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
January 2, 2019	2.5	%	5.00	2.9	%	23.96	%	$	4.40
January 2, 2018	2.2	%	5.00	2.3	%	23.45	%	$	5.02
January 3, 2017	1.9	%	5.00	2.6	%	24.49	%	$	4.20
April 19, 2016	1.3	%	5.00	2.6	%	26.34	%	$	4.09
April 21, 2015	1.3	%	5.00	2.7	%	26.84	%	$	3.68
April 22, 2014	1.8	%	5.00	2.0	%	28.55	%	$	4.79
April 16, 2013	0.7	%	5.00	1.6	%	37.42	%	$	6.33
April 17, 2012	0.9	%	5.00	1.4	%	39.25	%	$	6.85
April 19, 2011	2.1	%	5.00	1.6	%	39.33	%	$	5.60

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 per share calculation because they were anti-dilutive:

	Nine-month Period		Three-month Period
Reconciliation	2019	2018	2019	2018
Basic weighted average shares outstanding	572,934,475	574,526,758	573,452,002	574,013,820
Weighted shares assumed upon exercise of stock options	1,042,830	390,058	914,771	512,624
Diluted weighted average shares outstanding	573,977,305	574,916,816	574,366,773	574,526,444

Anti-Dilutive Options Excluded

	Nine-month Period			Three-month Period
Summary of Anti-dilutive Options Excluded	2019		2018	2019		2018
Options to purchase shares of common stock	460,824		3,194,684	553,366		3,069,590
Weighted average exercise prices of options	$	27.55	27.51	$	27.59	27.51