Amounts of common stock included in plan assets

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- Definition

Defined Benefit Plan, Assumed Asset Rate of Return, Percentage

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- Definition

Defined benefit plan weighted average expected return on plan assets period.

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- Definition

Employee savings investment plan employer matched compensation percentage.

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- Definition

Employee Savings Investment Plan Minimum Age Requirement.

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- Definition

Employee Stock Purchase Plan Contributions.

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No definition available.

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- Definition

Employee Stock Purchase Plan Shares Purchased.

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No definition available.

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Percentage of employee stock purchase plan contribution.

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Percentage of employee stock purchase plan employer contribution.

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- Definition

Target Funding Level Expected Return.

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Target Funding Level Expected Return Risk Annual Decline.

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Target Funding Level Expected Return Risk Level.

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- Definition

Target Funding Level Percentage.

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Target Funding Level Years.

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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)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

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.

+ References

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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.

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

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(7)
-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 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
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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No definition available.

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Amount of contributions made to multiemployer plan by employer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
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Pension and Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan, additional pension expense	$ 5	$ 5	$ 5
Defined benefit plan, pension settlement charges	14
Amounts of common stock included in plan assets	189	177
Defined benefit plan, estimated employer contributions	$ 18
Employee Savings Investment Plan, minimum age requirement	21 years
Maximum contribution percent by employer	50.00%
Employer matching contribution, percent of employee's gross pay	3.00%
Total contributions	$ 2	$ 2	$ 2
Percentage of employee stock purchase plan, employee contribution	85.00%
Percentage of employee stock purchase plan, employer contribution	15.00%
Shares purchased under employee stock purchase plan (in shares)	25,511	26,299
Employee stock purchase plan, company contribution (less than)	$ 1	$ 1
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated net losses of pensions in following twelve months	93
Estimated prior service credits of pensions in following twelve months	(10)
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated net losses of pensions in following twelve months	4
Estimated prior service credits of pensions in following twelve months	$ (37)
Non-U.S. Plans \| Pension Plan \| United Kingdom
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Funding level	100.00%
Target funding level period	9 years
Expected return net of fees	2.00%
Percentage change of risk level commensurate	5.00%
Weighted average return of equity securities period (years)	25 years
Non-U.S. Plans \| Pension Plan \| United Kingdom \| Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Yearly rate of funding level decline	4.00%
Non-U.S. Plans \| Pension Plan \| United Kingdom \| Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Yearly rate of funding level decline	7.00%
Non-U.S. Plans \| Pension Plan \| United Kingdom \| Debt securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed rate of return on assets, percentage	2.50%
Non-U.S. Plans \| Pension Plan \| United Kingdom \| Real estate
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed rate of return on assets, percentage	5.00%
Non-U.S. Plans \| Pension Plan \| United Kingdom \| Equity securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed rate of return on assets, percentage	8.50%
U.S. Plans \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Weighted average return of equity securities period (years)	25 years
U.S. Plans \| Pension Plan \| Equity securities and alternative investments [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed rate of return on assets, percentage	9.20%
U.S. Plans \| Pension Plan \| Debt securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed rate of return on assets, percentage	4.20%
U.S. Plans \| Pension Plan \| Real estate
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed rate of return on assets, percentage	5.00%