Pension and Postretirement Benefit Plans and Defined Contribution Plans - Funded Status Recognized in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent assets	$ 0	$ 0
Current liabilities	(24)	(29)
Noncurrent liabilities	(1,124)	(1,371)
Funded status	(1,148)	(1,401)
Foreign Plan [Member] \| Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent assets	453	401
Current liabilities	(30)	(28)
Noncurrent liabilities	(2,526)	(2,111)
Funded status	(2,103)	(1,738)
Qualified Plan [Member] \| United States [Member] \| Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent assets	0	0
Current liabilities	0	(1)
Noncurrent liabilities	(1,949)	(2,088)
Funded status	(1,949)	(2,089)
Nonqualified Plan [Member] \| United States [Member] \| U.S. Supplemental (Non-Qualified) Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent assets	0	0
Current liabilities	(189)	(167)
Noncurrent liabilities	(1,162)	(1,113)
Funded status	$ (1,351)	$ (1,280)

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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