Shareholders' Equity (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
Defined benefit and other postretirement liability adjustments	$ (203)	$ (203)
Cumulative translation adjustments	(82)	(82)
Other	(67)	(70)
Total accumulated other comprehensive loss	$ (352)	$ (355)

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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