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Pension and Other Postretirement Benefit Plans - Retirement Plan Weighted Average Asset Allocations (Details) - Retirement Plan [Member] | Dec. 31, 2020 | Dec. 31, 2019
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Equity Securities [Member] |  |
Weighted average asset allocation | 0.00% | 0.00%
Debt Securities [Member] |  |
Weighted average asset allocation | 100.00% | 100.00%

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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=118255775&loc=d3e1928-114920 + Details
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- Details
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- Details
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- Details
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