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Recent Authoritative Accounting Guidance (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2018 USD ($)
Retained earnings | ASU 2018-02 |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Reclassification of the income tax effects of the Tax Cut and Jobs Act from AOCI | $ 3.1

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