Related Party Transactions (Due to Related Parties, Net) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Balance, Beginning				$ (1,036)
Management fee expense incurred		$ (1,095)	$ (628)	(2,176)	$ (1,256)	$ (1,064)
Management fees paid to Advisor	[1]			2,145
Loan to Advisor				33
Loan to other related party				80	$ (40)
Balance, Ending		(987)		(987)		(1,036)
Due To Advisor Mgmt Fees [Member]
Related Party Transaction [Line Items]
Balance, Beginning				(1,064)
Management fee expense incurred	[1]			(2,176)
Management fees paid to Advisor	[1]			2,145
Loan to Advisor				0
Loan to other related party				0
Balance, Ending		(1,095)		(1,095)		(1,064)
Due To Advisor Other Funds [Member]
Related Party Transaction [Line Items]
Balance, Beginning				9
Management fee expense incurred	[1]			0
Management fees paid to Advisor	[1]			0
Loan to Advisor				33
Loan to other related party				0
Balance, Ending		42		42		9
Due to from Other Related party [Member]
Related Party Transaction [Line Items]
Balance, Beginning				19
Management fee expense incurred	[1]			0
Management fees paid to Advisor	[1]			0
Loan to Advisor				0
Loan to other related party				47
Balance, Ending		$ 66		$ 66		$ 19

[1] Net amount accrued of $31 consists of $2,176 in management fee expense incurred, net of $2,145 of accrued management fees that were paid to the Advisor. This represents a cash flow operating activity.