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Retirement Benefits (Details 13) - Pension Benefits [Member] | 12 Months Ended
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Dec. 31, 2018
Minimum [Member] | Global Equity Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .3
Minimum [Member] | Global debt securities and cash [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .15
Minimum [Member] | Private equity [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | 0
Minimum [Member] | Hedge funds [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .10
Minimum [Member] | Real estate and other [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | 0
Maximum [Member] | Global Equity Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .6
Maximum [Member] | Global debt securities and cash [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .4
Maximum [Member] | Private equity [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .15
Maximum [Member] | Hedge funds [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | .2
Maximum [Member] | Real estate and other [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target asset allocation | 0.1

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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. + References No definition available. + Details
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- Definition Description of investment policy and strategy for defined benefit plan asset. Includes, but is not limited to, investment allocation decision and factor pertinent to understanding investment policy and strategy for plan asset. Factor includes, but is not limited to, investment goal, risk management practice, permitted and prohibited investment including use of derivative, diversification, and relationship between plan asset and obligation. + 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=112275985&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=108410482&loc=d3e1928-114920 + Details
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