Stock-Based Compensation (Narratives) (Details) - USD ($) $ in Millions	3 Months Ended
Feb. 28, 2019	Feb. 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining contractual life of stock options outstanding	3 years 9 months 10 days
Weighted average remaining contractual life of stock options exercisable	3 years 7 months 15 days
Aggregate intrinsic value of stock options outstanding	$ 62.3
Aggregate intrinsic value of stock options exercisable	60.4
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, total	$ 0.1
Period for recognition	7 months 7 days
Stock-based compensation expense (income) associated with stock options, total		$ 0.2
Restricted Stock and Performance Unit Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense (income) associated with stock options, total	$ 4.1	$ 3.7

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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