Acquisitions and Divestitures (Narrative) (Details) - USD ($) $ in Millions					3 Months Ended
	Feb. 29, 2016	Jan. 08, 2016	May. 18, 2015	Jan. 08, 2015	Mar. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Revenue period for earnout provision	5 years
2016 Asset Acquisition [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 23.6
Sanbolic, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Preliminary consideration				$ 89.4
Cash acquired in business combination				0.2
Transaction costs				$ 0.5
Conversion of assumed non-vested stock units to shares of Company stock (shares)				37,057
Grasshopper Group, LLC [Member]
Finite-Lived Intangible Assets [Line Items]
Preliminary consideration			$ 161.5
Cash acquired in business combination			3.6
Transaction costs			$ 0.3
Conversion of assumed non-vested stock units to shares of Company stock (shares)			105,765
General and Administrative Expense [Member] | Sanbolic, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Acquisition related costs					$ 0.2
General and Administrative Expense [Member] | Grasshopper Group, LLC [Member]
Finite-Lived Intangible Assets [Line Items]
Acquisition related costs			$ 0.3