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Employee Benefit Plans and Other Postretirement Benefits - Schedule of Pension Plan Asset Investments and Target Allocations (Details) | Dec. 31, 2018 | Jan. 05, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Fixed Income Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Fair Value | 53.00% | 52.00% | 21.00%
International Equity Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Fair Value | 27.00% | 28.00% | 6.00%
U.S. Equity Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Fair Value | 18.00% | 20.00% | 9.00%
Other Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Fair Value | 2.00% |  | 64.00%

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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 Percentage of actual 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/2009/role/commonPracticeRef -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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