Acquisitions (Recognized Amounts of Identified Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Purchase consideration		$ 841
Goodwill		1,936	$ 1,694	$ 1,577
Optical Communications [Member]
Goodwill		926	671	645
Display Technologies [Member]
Goodwill		132	$ 136	$ 126
Communications Market Division [Member]
Property, plant and equipment		32
Other intangible assets		525
Other net assets		16
Total identified net assets		573
Purchase consideration		841
Goodwill	[1],[2]	$ 268

[1] Amounts reflect measurement period adjustments.

[2] The goodwill recognized is deductible for U.S. income tax purposes. The goodwill was allocated to the Optical Communications segment.