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Indebtedness - Schedule of Outstanding Indebtedness (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jun. 28, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Outstanding indebtedness	$ 25,433		$ 276,000
Unamortized net premiums, discounts and deferred financing fees	258		(1,045)
Total	$ 25,691		274,955
206 East 9th Street \| Secured Debt
Debt Instrument [Line Items]
Interest rate stated percentage	5.69%
Outstanding indebtedness	$ 25,433		26,000
5.875% Senior Unsecured Notes due 2020
Debt Instrument [Line Items]
Interest rate stated percentage		5.875%
5.875% Senior Unsecured Notes due 2020 \| Unsecured Debt
Debt Instrument [Line Items]
Interest rate stated percentage	0.00%	5.875%
Outstanding indebtedness	$ 0		$ 250,000