Consolidation of Variable Interest Entities - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017	Oct. 31, 2017
Variable Interest Entity [Line Items]
Restricted bank financial instruments under Buyer SPE	$ 50.9		$ 50.9		$ 50.9
Interest income of Buyer SPE	0.6	$ 0.6	1.2	$ 1.2
Net income (loss) attributable to noncontrolling interests	6.8	3.9	10.4	6.5
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Net income (loss) attributable to noncontrolling interests	4.4	1.2	$ 5.5	1.8
Buyer Spe
Variable Interest Entity [Line Items]
Ownership interest			0.00%
STA Timber
Variable Interest Entity [Line Items]
Debt instrument, principal outstanding	43.3		$ 43.3		$ 43.3
Interest expense	$ 0.6	$ 0.6	$ 1.2	$ 1.2