Inventory Impairments and Land Option Contract Abandonments (Narrative) (Details) $ in Millions	3 Months Ended	9 Months Ended
Aug. 31, 2026 USD ($) community	Aug. 31, 2025 USD ($) community	Aug. 31, 2026 USD ($) community	Aug. 31, 2025 USD ($) community	Nov. 30, 2025 USD ($) community
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of land parcels or communities evaluated for recoverability \| community	23		23		11
Carrying value of communities of land parcels evaluated for impairment	$ 316.1		$ 316.1		$ 154.1
Inventory impairment charges	$ 1.1	$ 7.3	$ 4.2	$ 7.3
Number of communities impaired \| community	1	1	2	1
Aggregate carrying value of inventory impacted by pretax, noncash inventory impairment charges	$ 24.0		$ 24.0		$ 38.0
Number of communities and various other land parcels impacted by pretax, noncash inventory impairment charges \| community	6		6		7
Land Option Contract Abandonment
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Land option abandonments	$ 1.9	$ 4.0	$ 6.5	$ 11.0

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Number of Communities Impaired

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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