Actual return on plan assets, separately identifying the amount related to assets sold during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ References

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ 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)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: 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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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ 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 (d)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(iv)(02)(B)

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- Definition

Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs.

+ 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 (d)(iv)(02)(C)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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-Subparagraph (c)(iv)(02)(C)

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Retirement Benefits - Changes in Level 3 Investments (Details) (USD $) In Millions, unless otherwise specified				12 Months Ended					12 Months Ended					12 Months Ended
	Dec. 31, 2013 US Plans [Member]	Dec. 31, 2012 US Plans [Member]	Dec. 31, 2011 US Plans [Member]	Dec. 31, 2013 US Plans [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2012 US Plans [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Non-US Plans [Member]	Dec. 31, 2012 Non-US Plans [Member]	Dec. 31, 2011 Non-US Plans [Member]	Dec. 31, 2013 Non-US Plans [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2012 Non-US Plans [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 UMWA Plans Postretirement Medical [Member]	Dec. 31, 2012 UMWA Plans Postretirement Medical [Member]	Dec. 31, 2011 UMWA Plans Postretirement Medical [Member]	Dec. 31, 2013 UMWA Plans Postretirement Medical [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2012 UMWA Plans Postretirement Medical [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Black Lung And Other Plans Postretirement [Member]	Dec. 31, 2012 Black Lung And Other Plans Postretirement [Member]	Dec. 31, 2011 Black Lung And Other Plans Postretirement [Member]	Dec. 31, 2013 Pension plan [Member]	Dec. 31, 2012 Pension plan [Member]	Dec. 31, 2011 Pension plan [Member]	Dec. 31, 2013 Retirement benefits other than pension [Member]	Dec. 31, 2012 Retirement benefits other than pension [Member]	Dec. 31, 2011 Retirement benefits other than pension [Member]
Changes in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 811.8	$ 756.3	$ 685.4	$ 99.3	$ 96.8	$ 322.0	$ 283.0	$ 230.5	$ 0.6	$ 0.6	$ 284.4	$ 268.7	$ 268.0	$ 40.9	$ 39.9	$ 0	$ 0	$ 0	$ 1,133.8	$ 1,039.3	$ 915.9	$ 284.4	$ 268.7	$ 268.0
Return on assets - relating to assets still held at the reporting date				0.4	2.5				0	0				0	1.0
Return on assets - relating to assets sold during the period				0						0				0
Purchases, sales and settlements				39.6					0					0
Transfers in and/or out of Level 3				(99.3)					(0.6)					(40.9)
Fair value of plan assets at end of year	$ 811.8	$ 756.3	$ 685.4	$ 40.0	$ 99.3	$ 322.0	$ 283.0	$ 230.5	$ 0	$ 0.6	$ 284.4	$ 268.7	$ 268.0	$ 0	$ 40.9	$ 0	$ 0	$ 0	$ 1,133.8	$ 1,039.3	$ 915.9	$ 284.4	$ 268.7	$ 268.0