Long-Term Incentive Plan (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Compensation expense and forfeitures
Capitalized compensation cost related to shares issued to design and construction employees	$ 99	$ 113
Restricted Shares
Compensation expense and forfeitures
Amortization Expense, including forfeitures	2,122	2,000
Capitalized compensation cost related to shares issued to design and construction employees	$ 100	$ 100
Restricted Shares \| Minimum
Long-Term Incentive Plan
Vesting period	3 years

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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