Fair Value Disclosures (Level 4 Inv Impair inputs) (Details 2) - Operating communities [Member] $ in Thousands	3 Months Ended
	Oct. 31, 2016 USD ($) Homes_sold	Jul. 31, 2016 USD ($) Homes_sold	Apr. 30, 2016 USD ($) Homes_sold	Jan. 31, 2016 USD ($) Homes_sold	Oct. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)	Apr. 30, 2015 USD ($)	Jan. 31, 2015 USD ($)
Minimum [Member]
Fair value inputs, assets, quantitative information [Line Items]
Average selling price	$ 0	$ 0	$ 369	$ 0	$ 301	$ 788	$ 527	$ 289
Sales Pace	0	0	18	0	3	4	13	1
Fair Value Inputs, Discount Rate	0.00%	0.00%	16.30%	0.00%	16.30%	15.50%	17.00%	13.50%
Maximum [Member]
Fair value inputs, assets, quantitative information [Line Items]
Average selling price	$ 0	$ 0	$ 394	$ 0	$ 764	$ 1,298	$ 600	$ 680
Sales Pace	0	0	23	0	24	8	25	7
Fair Value Inputs, Discount Rate	0.00%	0.00%	16.30%	0.00%	22.00%	16.20%	17.00%	16.00%