Share and Unit-based Plans - Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share and unit-based plans
Compensation cost under share and unit-based plans	$ 16,723	$ 33,551	$ 37,005
Capitalized share and unit-based compensation costs	4,691	6,184	6,206
Stock units
Share and unit-based plans
Compensation cost under share and unit-based plans	4,598	6,355	6,045
Unrecognized compensation cost of share and unit-based plans	2,949
LTIP units
Share and unit-based plans
Compensation cost under share and unit-based plans	11,372	26,311	30,161
Unrecognized compensation cost of share and unit-based plans	1,647
Stock options
Share and unit-based plans
Compensation cost under share and unit-based plans	51	125	85
Unrecognized compensation cost of share and unit-based plans	0
Phantom stock units
Share and unit-based plans
Compensation cost under share and unit-based plans	702	760	714
Stock awards and units
Share and unit-based plans
Fair value of equity-based awards vested during period	$ 3,577	$ 6,479	$ 5,257

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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