Defined benefit plan target and weighted average asset allocations for US pension plans.

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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.

+ 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)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Retirement Benefit Plans - Target Allocation (Details) - Pension Plan [Member]	Dec. 31, 2017	Dec. 31, 2016
Target assets allocation and actual asset allocations for US pension plan assets
Actual Asset Allocation	100.00%	100.00%
Equity securities [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Actual Asset Allocation	14.00%	12.00%
Debt Securities [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Actual Asset Allocation	80.00%	78.00%
Other Investments [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Actual Asset Allocation	6.00%	10.00%
Minimum [Member] \| Equity securities [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Current Target Allocation	10.00%
Minimum [Member] \| Debt Securities [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Current Target Allocation	70.00%
Minimum [Member] \| Other Investments [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Current Target Allocation	4.00%
Maximum [Member] \| Equity securities [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Current Target Allocation	16.00%
Maximum [Member] \| Debt Securities [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Current Target Allocation	90.00%
Maximum [Member] \| Other Investments [Member]
Target assets allocation and actual asset allocations for US pension plan assets
Current Target Allocation	10.00%