The interest rate used to adjust for the time value of money, used for service cost.

No definition available.

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- Definition

The interest rate used to adjust for the time value of money, used for interest cost.

+ References

No definition available.

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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.

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- Definition

Amount of cost recognized for passage of time related to 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 (h)(2)
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-Publisher FASB
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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

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

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
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Pension Plans, Retirement Benefits and Savings Plans (details) - Change in Estimation - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Change in Accounting Estimate
Increase in diluted net income per share	$ 1.98	$ 1.05	$ 2.11	$ 2.17	$ 3.28	$ 2.45	$ 2.24	$ 2.30	$ 7.33	$ 10.28	$ 10.88
Pension Plans [Member]
Change in Accounting Estimate
Reduction to service cost									$ (119)	$ (118)	$ (131)
Reduction to interest cost									(127)	(122)	(144)
Pension Plans [Member] \| United States [Member] \| Qualified Plan [Member]
Change in Accounting Estimate
Reduction to service cost									(112)	(111)
Reduction to interest cost									$ (120)	$ (114)
Weighted average discount rate used to measure service cost (percent)									4.52%	4.77%
Weighted average discount rate used to measure interest cost (percent)									3.55%	3.64%
Pension Plans [Member] \| United States [Member] \| Nonqualified Plan [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)									4.24%	4.53%
Weighted average discount rate used to measure interest cost (percent)									3.43%	3.47%
Postretirement Benefit Plans [Member]
Change in Accounting Estimate
Reduction to interest cost									$ (7)	$ (8)	$ (10)
Postretirement Benefit Plans [Member] \| United States [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure interest cost (percent)									3.42%	3.53%
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Impact of Change in Estimation Approach [Member]
Change in Accounting Estimate
Reduction to service cost										$ 6
Reduction to interest cost										$ 30
Increase in diluted net income per share										$ 0.08
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Current Estimation Approach [Member] \| Pension Plans [Member] \| United States [Member] \| Qualified Plan [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)										4.77%
Weighted average discount rate used to measure interest cost (percent)										3.64%
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Current Estimation Approach [Member] \| Pension Plans [Member] \| United States [Member] \| Nonqualified Plan [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)										4.53%
Weighted average discount rate used to measure interest cost (percent)										3.47%
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Current Estimation Approach [Member] \| Postretirement Benefit Plans [Member] \| United States [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)										0.00%
Weighted average discount rate used to measure interest cost (percent)										3.53%
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Prior Estimation Approach [Member] \| Pension Plans [Member] \| United States [Member] \| Qualified Plan [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)										4.50%
Weighted average discount rate used to measure interest cost (percent)										4.50%
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Prior Estimation Approach [Member] \| Pension Plans [Member] \| United States [Member] \| Nonqualified Plan [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)										4.37%
Weighted average discount rate used to measure interest cost (percent)										4.37%
Change in Assumptions for Pension Plans and Postretirement Benefit Plans [Member] \| Prior Estimation Approach [Member] \| Postretirement Benefit Plans [Member] \| United States [Member]
Change in Accounting Estimate
Weighted average discount rate used to measure service cost (percent)										4.35%
Weighted average discount rate used to measure interest cost (percent)										4.35%