Income Taxes and Distributions (Tax Effects of Taxable and Deductible Temporary Differences) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Tax effect of temporary differences
Investments and property, primarily differences in investment basis, depreciation and amortization, the basis of land assets and the treatment of interests and certain costs	$ (2,533)	$ (11,812)	$ (7,089)
Operating loss and interest deduction carryforwards	98,713	94,654	82,469
Expense accruals and other	48,804	25,146	15,978
Valuation allowance	(155,592)	(127,283)	(96,838)	$ (98,966)
Net deferred tax assets (liabilities)	$ (10,608)	$ (19,295)	$ (5,480)