Company pension investments which are categorized as level three assets percentage.

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- Definition

Expected annual standard deviation in returns of the target portfolio which reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests.

+ References

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from assets transferred into (from) plan.

+ References

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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.

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No definition available.

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (s)
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Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

Amount of cost for defined contribution plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
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Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 20,500	$ 18,400
Percentage of Company's pension investments categorized as Level 3 assets (as percent)		2.00%	2.00%
Employer contributions to defined contribution savings plans		$ 131	$ 126	$ 125
United States
Defined Benefit Plan Disclosure [Line Items]
Expected annual standard deviation in returns of the target portfolio which reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests (as percent)		13.00%
United States \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)		8.00%
United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)		8.75%
Forecast \| United States \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)	7.70%
Forecast \| United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)	8.30%
U.S. Equity Securities \| United States \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		35.00%
U.S. Equity Securities \| United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		55.00%
International Securities \| United States \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		20.00%
International Securities \| United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		35.00%
Fixed Income Investments \| United States \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		20.00%
Fixed Income Investments \| United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		35.00%
Cash And Other Investments \| United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		5.00%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Assets no longer restricted to the payment of postretirement benefits		$ 0	992
Fair value of plan assets		1,114	1,019	1,913
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		25
Estimated net loss (gain) amounts that will be amortized from AOCI into net pension and postretirement benefit cost during next fiscal year		1
Estimated prior service cost (credit) amounts that will be amortized from AOCI into net pension and postretirement benefit cost during next fiscal year		(84)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Estimated net loss (gain) amounts that will be amortized from AOCI into net pension and postretirement benefit cost during next fiscal year		314
Estimated prior service cost (credit) amounts that will be amortized from AOCI into net pension and postretirement benefit cost during next fiscal year		(64)
Pension Plan \| Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		488	435
International \| Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Assets no longer restricted to the payment of postretirement benefits		0	0
Fair value of plan assets		9,339	$ 7,794	$ 7,204
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		$ 150
Expected rate of return on plan assets (as percent)		5.10%	5.60%	5.70%
United States
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)		8.70%	8.60%	8.50%
United States \| Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Assets no longer restricted to the payment of postretirement benefits		$ 0	$ 0
Accumulated benefit obligation		11,500	10,500
Fair value of plan assets		10,896	$ 9,766	$ 9,266
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		60
Estimated net loss (gain) amounts that will be amortized from AOCI into net pension and postretirement benefit cost during next fiscal year		230
Estimated prior service cost (credit) amounts that will be amortized from AOCI into net pension and postretirement benefit cost during next fiscal year		$ (51)