Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Related Party Transactions - Schedule of Amount Contractually Due and Forgiven in Connection With Operation Related Services (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Advisor \| Variable Base Management Fee
Related Party Transaction [Line Items]
Related party expenses	$ 2,200	$ 1,200
Incurred
Related Party Transaction [Line Items]
Related party expenses	8,043	6,831
Forgiven
Related Party Transaction [Line Items]
Related party expenses	0	0
Payable
Related Party Transaction [Line Items]
Related party payable	0		$ 49
Nonrecurring Fees \| Fees on gain from sale of investments \| Incurred
Related Party Transaction [Line Items]
Related party expenses	0	0
Nonrecurring Fees \| Fees on gain from sale of investments \| Forgiven
Related Party Transaction [Line Items]
Related party expenses	0	0
Nonrecurring Fees \| Fees on gain from sale of investments \| Payable
Related Party Transaction [Line Items]
Related party payable	0		49
Recurring Fees \| Asset management fees \| Incurred
Related Party Transaction [Line Items]
Related party expenses	6,671	5,659
Recurring Fees \| Asset management fees \| Forgiven
Related Party Transaction [Line Items]
Related party expenses	0	0
Recurring Fees \| Asset management fees \| Payable
Related Party Transaction [Line Items]
Related party payable	0		0
Recurring Fees \| Property management fees
Related Party Transaction [Line Items]
Related party expenses		0
Recurring Fees \| Property management fees \| Incurred
Related Party Transaction [Line Items]
Related party expenses	1,372	1,172
Recurring Fees \| Property management fees \| Forgiven
Related Party Transaction [Line Items]
Related party expenses	0	0
Recurring Fees \| Property management fees \| Payable
Related Party Transaction [Line Items]
Related party payable	0		0
Recurring Fees \| Incentive compensation \| Incurred
Related Party Transaction [Line Items]
Related party expenses	0	0
Recurring Fees \| Incentive compensation \| Forgiven
Related Party Transaction [Line Items]
Related party expenses	0	0
Recurring Fees \| Incentive compensation \| Payable
Related Party Transaction [Line Items]
Related party payable	0		$ 0
General and Administrative Expense \| Incurred
Related Party Transaction [Line Items]
Related party expenses	$ 300	$ 9