Related Party Transactions and Arrangements (Fees Incurred in Connection With the Operations of the Company, Incurred and Payable) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	$ 25,695	$ 23,143	$ 20,908
General and administrative	20,375	22,733	19,691
Acquisition fees and related cost reimbursements
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	241	318	180
Payable	53	70
Vesting and conversion of Class B Units
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	0	15,786	0
Payable	0	0
Asset management fees to related party
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	25,695	23,143	20,908
Payable	9	95
Property management and leasing fees
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	9,921	9,620	7,167
Payable	1,153	1,272
Professional fees and other reimbursements
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	9,732	9,314	8,540
Payable	(565)	1,197
Distributions on Class B Units
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	0	736	1,551
Payable	0	0
Total related party operation fees and reimbursements
Related Party Transaction [Line Items]
Total commissions and fees from the Former Dealer Manager	45,589	58,917	$ 38,346
Payable	650	2,634
American National Stock Transfer, LLC \| Accounts Payable
Related Party Transaction [Line Items]
General and administrative	800
Revenue from related parties		$ 800
Advisor \| Professional fees and other reimbursements
Related Party Transaction [Line Items]
Related party transaction, due from (to) related party	$ 700

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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