Inventory Impairments and Land Option Contract Abandonments (Narratives) (Details)		3 Months Ended		9 Months Ended
		Aug. 31, 2020 USD ($) lot delivery Rate	Aug. 31, 2019 USD ($) delivery Rate	Aug. 31, 2020 USD ($) lot delivery property Rate	Aug. 31, 2019 USD ($) delivery property Rate	Nov. 30, 2019 USD ($) property
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Number of land parcels or communities evaluated for recoverability | property				22	31
Carrying value of communities or land parcels evaluated for impairment		$ 191,800,000	$ 219,200,000	$ 191,800,000	$ 219,200,000
Inventory impairment charges		$ 6,500,000	$ 4,800,000	11,600,000	$ 11,500,000
Deliveries per month | delivery	[1]	2
Aggregate carrying value of inventory impacted by pretax, noncash inventory impairment charges		$ 89,400,000		$ 89,400,000		$ 115,600,000
Number of communities and various other land parcels impacted by pretax, noncash inventory impairment charges		16		16		19
Measurement Input, Discount Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount Rate, Percent | Rate	[1]		17.00%		17.00%
Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Average Selling price	[1]	$ 301,600	$ 325,300	$ 301,600	$ 315,000
Deliveries per month | delivery	[1]		2	1	1
Minimum [Member] | Measurement Input, Discount Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount Rate, Percent | Rate	[1]	17.00%		17.00%
Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Average Selling price	[1]	$ 1,010,100	$ 957,200	$ 1,010,100	$ 1,045,400
Deliveries per month | delivery	[1]		4	4	4
Maximum [Member] | Measurement Input, Discount Rate [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount Rate, Percent | Rate	[1]	18.00%		18.00%
Land Option Contract Abandonment [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Land option contract abandonment charges		$ 400,000	$ 400,000	$ 5,400,000	$ 1,700,000

[1] The ranges of inputs used in each period primarily reflect differences between the housing markets where each impacted community is located, rather than fluctuations in prevailing market conditions.