Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Housing Completed or Under Construction [Member]
Net changes in assets and liabilities:
Housing completed or under construction	$ (115,357,000)	$ 4,282,000
Land and Land Under Development [Member]
Net changes in assets and liabilities:
Housing completed or under construction	68,311,000	(1,274,000)
Net income	9,563,000	8,420,000
Stock-based compensation expense	2,987,000	875,000
Depreciation and amortization	$ 1,073,000	1,083,000
Inventory impairments		350,000
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ 431,000	0
Loss on sale of marketable securities	$ 915,000	11,000
Amortization of discount / premiums on marketable debt securities, net		59,000
Deferred income tax expense	$ 1,788,000	4,713,000
Restricted cash	401,000	(1,444,000)
Trade and other receivables	(15,251,000)	(6,141,000)
Mortgage loans held-for-sale	33,477,000	23,684,000
Prepaid expenses and other assets	911,000	489,000
Accounts payable and accrued liabilities	(4,234,000)	(19,681,000)
Net cash provided by (used in) operating activities	(14,985,000)	15,426,000
Investing Activities:
Purchases of marketable securities	$ (5,482,000)	(20,484,000)
Maturities of marketable securities		1,510,000
Sales of marketable securities	$ 20,600,000	12,976,000
Purchases of property and equipment	(1,944,000)	(340,000)
Net cash provided by (used in) investing activities	13,174,000	(6,338,000)
Financing Activities:
Payments on mortgage repurchase facility, net	(28,390,000)	(20,785,000)
Dividend payments	(12,252,000)	(12,213,000)
Net cash used in financing activities	(40,642,000)	(32,998,000)
Net decrease in cash and cash equivalents	(42,453,000)	(23,910,000)
Cash and cash equivalents:
Beginning of period	180,988,000	153,825,000
End of period	$ 138,535,000	$ 129,915,000