The actual investment return on assets of defined benefit plans in percentage terms

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Defined Benefit Plan, Buy-out of Balances, Number of Participants Affected

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Defined Contribution Plan, Employers Contribution

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Amount of dividends received on employer stock held in defined benefit plan

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Amount in percentage terms of the plan assets of the US Qualified defined benefit plan to the total assets of all defined benefit plans

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- Definition

Percent of Current Year Contributions to Plan that Company Contributions Exceed

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- Definition

Estimated retirement benefit expense in next fiscal year

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accumulated Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: 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=65897934&loc=d3e1928-114920

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- Definition

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: 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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-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Amount of contributions made by the employer to defined benefit plans.

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-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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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 30
-Section 35
-Paragraph 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6749337

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-Name Accounting Standards Codification
-Glossary Plan Assets
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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Health Care Cost Trend Rate
-URI http://asc.fasb.org/extlink&oid=6514820

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The number of employer shares or related party shares included in plan assets.

+ References

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- Definition

Changes in the defined benefit obligation, not otherwise separately disclosed in the financial statements.

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No definition available.

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- Definition

The ultimate trend rate for health care costs.

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

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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.

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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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
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- Definition

Percentage employer matches of the employee's percentage contribution matched.

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No definition available.

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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258

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Retirement Benefits - Narrative (Details) shares in Millions, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Jul. 31, 2016 USD ($)	Dec. 31, 2012	Dec. 31, 2017	Dec. 31, 2016 USD ($) retiree shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)	Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions	$ 115.0
Projected Retirement Benefit Expense In Next 12 months				$ 71.0
Defined contribution plan- Company contribution (percent)					6.50%
Defined contribution plan- Company matching contribution (percent)					3.00%
Other postretirement benefit costs for a defined contribution plan				34.5	$ 41.2	$ 21.9
US Qualified Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated employer contributions in next 12 months				$ 135.0
Percentage of total assets				96.00%
Number of shares of equity securities issued by employer included in plan assets \| shares				3.0	3.0
Fair value of employer equity securities included in plan assets				$ 47.1	$ 33.2
Dividends on employer stock received by plan				0.7	1.8
Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions				125.1	10.3
Projected Retirement Benefit Expense In Next 12 months				$ 48.0
Number of retirees removed from plan through annual buy-out \| retiree				3,700
Benefits paid for small annuity buyout				$ 47.0
Accumulated benefit obligation				$ 2,710.7	$ 2,767.0
Expected long-term rate of return on assets				8.00%	8.00%	8.25%
Actual return on plan assets		8.00%		5.30%	(1.20%)	6.50%	14.30%
Fair value of plan assets				$ 1,894.6	$ 1,962.3	$ 2,204.4
Other Pension Plans, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated employer contributions in next 12 months				10.0
Other Postretirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions				0.0	$ 0.0
Projected Retirement Benefit Expense In Next 12 months				$ 23.0
Assumed increase in per capita cost of covered benefits in next 12 months				7.20%
Assumed ultimate health care cost trend rate				4.50%
Year that ultimate trend rate is reached				2038
Expected long-term rate of return on assets				4.00%	4.00%	8.30%
Fair value of plan assets				$ 0.7	$ 1.8	$ 2.9
Global debt securities and cash [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Unfunded commitments				124.0
Private equity [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Unfunded commitments				102.0
Fair value of plan assets				204.1	201.2
Real estate and other [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Unfunded commitments				11.0
Fair value of plan assets				96.5	186.5
Fair Value, Inputs, Level 3 [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets				99.3	305.6	361.3
Fair Value, Inputs, Level 3 [Member] \| Private equity [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets				0.0	0.0
Fair Value, Inputs, Level 3 [Member] \| Private equity [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets				0.7
Fair Value, Inputs, Level 3 [Member] \| Real estate and other [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets				$ 0.0	$ 0.0
Other Postretirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Other postretirement benefit costs for a defined contribution plan						$ 2.6
Forecast [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected long-term rate of return on assets			7.75%
Forecast [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected long-term rate of return on assets			4.00%
MultiemployerPlan1 [Member] \| Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percent of Current Year Contributions to Plan that Company Contributions Exceed					5.00%