Accounting Pronouncements Adoption of New Accounting Pronouncements (Details) - Accounting Standards Update 2018-02 $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of tax effects from AOCI to retained earnings	$ 0.3
AOCI Attributable to Parent
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of tax effects from AOCI to retained earnings	$ (0.3)

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.

No definition available.

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