Pension and Postretirement Benefit Plans - Pension Asset Fair Value Level 3 (Details) - Qualified and Non-qualified Pension Benefits - International - Funded - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Benefit Plan Information
Foreign currency exchange	$ 346	$ (560)
Level 3
Benefit Plan Information
Foreign currency exchange	(13)	16
Defined benefit plan increases related to net purchases and unrealized gains losses		$ 48
Defined benefit plan decreases related to net purchases and unrealized gains losses	$ (11)

This represents the decrease in plan assets related to net purchases and unrealized gains/losses.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

This represents the increase in plan assets related to net purchases and unrealized gains/losses.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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- Details

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- Details

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- Details

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- Details

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