Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	Jan. 16, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Cash Flows [Abstract]
Accrued distributions payable		$ 5,667	$ 5,846	$ 4,700
Accrued but unpaid distribution		500	800	500
Accounts payable and accrued expenses		2,400	2,400	2,000
Accrued share based compensation		$ 500	$ 500	$ 600
Subsequent Event
Shares issued pursuant to equity incentive plan (in shares)	27,870

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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