CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2017
Provision (benefit) for income taxes	$ (8.2)			$ (14.1)
Pension and postretirement adjustments, tax portion	$ 0.0	$ 0.8	$ 0.0	$ 14.1	$ 6.3	$ 0.1
ASU 2014-09
Provision (benefit) for income taxes			$ 16.0
Common Class A
Dividends declared per class A and common share (in Dollars per share)	$ 0.15	$ 0.15	$ 0.15	$ 0.15	$ 0.15	$ 0.15

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

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