Fair Value Disclosures (Level 4 inventory fv) (Details 3) $ in Thousands	3 Months Ended												12 Months Ended
	Oct. 31, 2020 USD ($) numberOfCommunities	Jul. 31, 2020 USD ($) numberOfCommunities	Apr. 30, 2020 USD ($) numberOfCommunities	Jan. 31, 2020 USD ($) numberOfCommunities	Oct. 31, 2019 USD ($) numberOfCommunities	Jul. 31, 2019 USD ($) numberOfCommunities	Apr. 30, 2019 USD ($) numberOfCommunities	Jan. 31, 2019 USD ($) numberOfCommunities	Oct. 31, 2018 USD ($) numberOfCommunities	Jul. 31, 2018 USD ($) numberOfCommunities	Apr. 30, 2018 USD ($) numberOfCommunities	Jan. 31, 2018 USD ($) numberOfCommunities	Oct. 31, 2020 USD ($)	Oct. 31, 2019 USD ($)	Oct. 31, 2018 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Inventory impairments and write-offs													$ 55,883	$ 42,360	$ 35,156
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Operating communities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of Operating Communities Tested | numberOfCommunities	53	66	80	65	71	69	64	49	43	55	65	64
Number of Communities impaired | numberOfCommunities	1	0	1	0	7	3	6	5	6	5	4	5
Fair Value Of Communities Net Of Impairment Charges	$ 1,113	$ 0	$ 2,754	$ 0	$ 18,910	$ 5,436	$ 36,159	$ 37,282	$ 24,692	$ 43,063	$ 21,811	$ 13,318	1,113	18,910	24,692
Inventory impairments and write-offs	$ 375	$ 0	$ 300	$ 0	$ 6,695	$ 1,100	$ 17,495	$ 5,785	$ 4,025	$ 9,065	$ 13,325	$ 3,736	$ 675	$ 31,075	$ 30,151