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Basis of Presentation Narrative (Details) $ in Millions | Jan. 01, 2018 USD ($)
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Retained Earnings [Member] | Accounting Standards Update 2016-01 [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Cumulative Effect of New Accounting Principle in Period of Adoption | $ 17.7
Retained Earnings [Member] | Accounting Standards Update 2018-02 [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Cumulative Effect of New Accounting Principle in Period of Adoption | (35.9)
AOCI Attributable to Parent [Member] | Accounting Standards Update 2016-01 [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Cumulative Effect of New Accounting Principle in Period of Adoption | (17.7)
AOCI Attributable to Parent [Member] | Accounting Standards Update 2018-02 [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Cumulative Effect of New Accounting Principle in Period of Adoption | $ 35.9

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