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Retirement and Other Postretirement Benefit Plans - Schedule of Actual Allocations for the Pension Assets and Target Allocations by Asset Class (Details) | Dec. 31, 2019 | Dec. 31, 2018
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Change in plan assets: |  |
Percentage of Plan Assets | 100.00% | 100.00%
Target Allocations | 100.00% | 100.00%
Diversified Growth Funds |  |
Change in plan assets: |  |
Percentage of Plan Assets | 25.90% | 24.10%
Target Allocations | 22.30% | 28.00%
Index Linked Gilts |  |
Change in plan assets: |  |
Percentage of Plan Assets | 34.30% | 30.90%
Target Allocations | 33.40% | 12.60%
Fixed Interest Gilts |  |
Change in plan assets: |  |
Percentage of Plan Assets | 9.30% |
Target Allocations | 9.10% |
Liability Driven Investments |  |
Change in plan assets: |  |
Percentage of Plan Assets | 13.80% | 17.20%
Target Allocations | 16.50% | 23.20%
All Other Regions Equity Fund |  |
Change in plan assets: |  |
Percentage of Plan Assets | 9.20% | 14.40%
Target Allocations | 10.80% | 19.70%
U.K. Equity Fund |  |
Change in plan assets: |  |
Percentage of Plan Assets | 4.00% | 9.70%
Target Allocations | 4.70% | 13.20%
Diversified Investment, Funds |  |
Change in plan assets: |  |
Percentage of Plan Assets | 1.10% | 1.10%
Target Allocations | 1.10% | 1.10%
Insurance contracts |  |
Change in plan assets: |  |
Percentage of Plan Assets | 2.00% | 2.30%
Target Allocations | 2.10% | 2.20%
Cash and Cash Equivalents |  |
Change in plan assets: |  |
Percentage of Plan Assets | 0.40% | 0.30%

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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/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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