Recent Authoritative Accounting Guidance (Details) $ in Millions	9 Months Ended
Sep. 30, 2017 USD ($)
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Reduction in income tax expense	$ 2.4
Excess tax benefits related to outstanding stock option awards	1.9
Excess tax benefits related to vesting of restricted stock	$ 0.5

Effective Income Tax Rate Reconciliation, Share-based Compensation, Restricted Stock Vested, Excess Tax Benefit, Amount

No definition available.

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