Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions								3 Months Ended		12 Months Ended
	Feb. 05, 2020	Feb. 04, 2020	Feb. 06, 2019	Feb. 05, 2019	Feb. 06, 2018	Feb. 05, 2018	Jan. 15, 2014	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 17, 2019	Apr. 26, 2018	Dec. 31, 2016
Treasury Stock, Shares, Acquired										31,000,000.0		84,400,000
Treasury Stock, Value, Acquired										$ 925	$ 2,230	$ 2,448
Preferred Stock, Par or Stated Value Per Share										$ 100	$ 100
Payments for Repurchase of Common Stock										$ 940	$ 2,227	$ 2,452
The 2016 Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount															$ 4,000
Treasury Stock, Shares, Acquired								17,200,000	17,100,000
Treasury Stock, Value, Acquired								$ 500	$ 500
The 2017 ASR Agreement [Member]
Treasury Stock, Shares, Acquired												50,100,000
Treasury Stock, Value, Acquired												$ 1,400
The 2018 Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount														$ 2,000
The 2016 and 2018 Repurchase Program [Member]
Treasury Stock, Shares, Acquired											74,800,000
Payments for Repurchase of Common Stock											$ 2,200
2019 Repurchase Authorization [Member]
Stock Repurchase Program, Authorized Amount													$ 5,000
Common Stock [Member]
Percentage increase of dvidend declared			11.10%		16.10%
Dividends declared per common share			$ 0.20	$ 0.18	$ 0.18	$ 0.155
Convertible Preferred Stock, Shares Issued upon Conversion							50,000
Convertible Preferred Stock, Threshold Trading Days							25 days
Convertible Preferred Stock, Threshold Consecutive Trading Days							40 days
Minimum Closing Price of Common Stock for the Company to Exercise Option to Convert Preferred Stock							$ 35
Common Stock [Member] | Subsequent Event [Member]
Percentage increase of dvidend declared	10.00%
Dividends declared per common share	$ 0.22	$ 0.20
Series A Convertible Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage							4.25%
Series A Convertible Preferred Stock [Member] | Samsung Corning Precision Materials Co., Ltd. [Member]
Stock Issued During Period, Shares, Acquisitions							1,900
Share Price							$ 1,000,000
Stock Issued During Period, Value, Acquisitions							$ 1,900
Stock Issued During Period, Value, New Issues							$ 400
Preferred Stock, Par or Stated Value Per Share							$ 100