Common Stock Repurchases (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2018	Aug. 31, 2017	Sep. 30, 2017
Common Stock Repurchases [Abstract]
Common stock repurchased and retired (in shares)	0.5	0.6	2.6	1.5
Common stock repurchased and retired	$ 20.0	$ 19.0	$ 110.0	$ 43.9
Stock repurchase authorization					$ 250.0
Remaining authorized repurchase amount	$ 110.0		$ 110.0

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Balance Type:	debit
Period Type:	duration