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New Accounting Pronouncements New Accounting Pronouncements (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
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Sep. 30, 2017 | Dec. 31, 2016
New Accounting Pronouncements [Abstract] |  |
Effect of Adoption on Share-Based Compensation | $ 0.5 | $ 1.1

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- Definition Effect of Adoption on Share-Based Compensation + References No definition available. + Details
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