Deferred Costs and Other Intangibles, Net - Components of Deferred Costs and Intangibles (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Acquired Indefinite-lived Intangible Assets
Deferred leasing costs	$ 9,741	$ 11,912
Deferred financing costs	11,244	11,246
Intangible assets:
Intangible assets	23,085	25,258
Less: accumulated amortization	(12,432)	(12,572)
Total	10,653	12,686
Database
Intangible assets:
Intangible assets	$ 2,100	$ 2,100