Investments in and advances to unconsolidated joint ventures - Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Cash and cash equivalents	$ 32,186	$ 45,945
Restricted cash	14,616	19,205
Real estate inventories	362,609	374,607
Other assets	5,329	4,231
Total assets	414,740	443,988
Accounts payable and accrued liabilities	37,794	43,158
Notes Payable	61,271	71,299
Liabilities	99,065	114,457
The Company's equity	32,362	33,617
Other partners' equity	283,313	295,914
Total equity	315,675	329,531
Total liabilities and equity	$ 414,740	$ 443,988
Debt-to-capitalization ratio	16.30%	17.80%
Debt-to-equity ratio	19.40%	21.60%