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Accumulated Other Comprehensive Income - Reclassification from AOCI Textuals (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Reclassification from other comprehensive income to earnings |  | $ (2.2) |  | $ (4.4)
Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Reclassification from other comprehensive income to earnings | $ (2.2) | $ (2.2) | $ (4.4) | $ (4.4)

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- Definition Net of tax amount of the income statement impact of the reclassification adjustment for actuarial (gains) losses and reclassification adjustment for prior service costs recognized as a component of net periodic benefit cost. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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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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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |