Stock Compensation - Effect on Shares Outstanding and Treasury Shares (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Change In Treasury Stock Roll Forward [Roll Forward]
Treasury stock (in shares)	808,784,381	795,665,646	757,657,217	744,831,978
Repurchases (in shares)	27,398,701	49,482,220	30,570,129
Total issued (in shares)	(14,208,395)	(11,468,610)	(17,740,140)
Director
Change In Treasury Stock Roll Forward [Roll Forward]
Director deferred stock units issued (in shares)	(71,571)	(5,181)	(4,750)
Employee Stock Option
Change In Treasury Stock Roll Forward [Roll Forward]
Exercised (in shares)	(11,529,174)	(8,432,458)	(13,313,019)
Stock applied to taxes (in shares)	0	0	0
Total issued (in shares)	(12,327,980)	(9,252,336)	(14,378,776)
Employee Stock Option | Director
Change In Treasury Stock Roll Forward [Roll Forward]
Director deferred stock units issued (in shares)	0	0	0
Restricted Stock Units (RSUs)
Change In Treasury Stock Roll Forward [Roll Forward]
Vested RSUs (in shares)	(2,370,762)	(2,769,994)	(4,419,464)
Stock applied to taxes (in shares)	490,347	553,720	1,058,100
Total issued (in shares)	(1,880,415)	(2,216,274)	(3,361,364)
Restricted Stock Units (RSUs) | Director
Change In Treasury Stock Roll Forward [Roll Forward]
Director deferred stock units issued (in shares)	0	0	0
Employee stock purchase plan
Change In Treasury Stock Roll Forward [Roll Forward]
Exercised (in shares)	(798,806)
Employee stock purchase plan | Employee Stock Option
Change In Treasury Stock Roll Forward [Roll Forward]
Exercised (in shares)	(798,806)	(819,878)	(1,065,757)
Employee stock purchase plan | Restricted Stock Units (RSUs)
Change In Treasury Stock Roll Forward [Roll Forward]
Vested RSUs (in shares)	0	0	0