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Recent Accounting Pronouncements (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2017 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2016 | Jan. 01, 2016
Item Effected [Line Items] |  |  |  |  |
Basic Earnings Per Share | $ 0.65 |  | $ 0.58 |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | $ 25.3
Excess Tax Benefit from Share-based Compensation, Operating Activities |  |  |  | $ 7.2 |
AccountingStandardsUpdate2016-09 |  |  |  |  |
Item Effected [Line Items] |  |  |  |  |
Basic Earnings Per Share |  | $ 0.00 | $ 0.02 |  |

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