Organization and Basis of Presentation - Additional Information (Detail)		6 Months Ended
	Apr. 30, 2019 USD ($) Installment $ / ft² shares	Jun. 30, 2019 USD ($) shares	Feb. 15, 2019 shares	Jan. 01, 2019 USD ($)	Dec. 31, 2018 shares
Organization And Basis Of Presentation [Line Items]
Capital stock, shares authorized | shares			80,000,000		31,428,571
Lease ROU assets | $		$ 142,000
Lease liabilities | $		$ 142,000
ASU 2016-02 [Member]
Organization And Basis Of Presentation [Line Items]
Lease ROU assets | $				$ 170,000
Lease liabilities | $				$ 170,000
2019 AMA [Member] | CDS [Member]
Organization And Basis Of Presentation [Line Items]
Fixed annual payment | $	$ 1,000,000
Agreement extended termination date	Dec. 31, 2027
Agreement original termination date	Dec. 31, 2022
Agreement additional extension term	1 year
Agreement notice period required for non-renewal	180 days
2019 AMA [Member] | CDS [Member] | Asset Management Fee [Member]
Organization And Basis Of Presentation [Line Items]
Percentage of CRE portfolio revenues	2.50%
2019 AMA [Member] | CDS [Member] | Construction Management Fee [Member]
Organization And Basis Of Presentation [Line Items]
Percentage of all costs associated with portfolio projects in development	4.00%
2019 AMA [Member] | CDS [Member] | Property Management Fee [Member]
Organization And Basis Of Presentation [Line Items]
Percentage of CRE portfolio revenues	1.00%
2019 AMA [Member] | CDS [Member] | Acquisition Fee [Member]
Organization And Basis Of Presentation [Line Items]
Maximum percentage of purchase price of an acquired asset	0.50%
2019 AMA [Member] | CDS [Member] | Disposition Fee [Member]
Organization And Basis Of Presentation [Line Items]
Percentage sales price of an asset on disposition	0.50%
2019 AMA [Member] | Comstock Asset Management, L.C. [Member]
Organization And Basis Of Presentation [Line Items]
Cumulative, compounded, preferred return rate	8.00%
Leasing fee per square foot for new leases | $ / ft²	1.00
Leasing fee per square foot for renewal leases | $ / ft²	0.50
2019 AMA [Member] | Comstock Asset Management, L.C. [Member] | Incentive Fee [Member]
Organization And Basis Of Presentation [Line Items]
Percentage of free cash flow from real estate assets	10.00%
2019 AMA [Member] | Comstock Asset Management, L.C. [Member] | Investment Origination Fee [Member]
Organization And Basis Of Presentation [Line Items]
Percentage of raised capital	1.00%
Business Management Agreement [Member] | Comstock Investors X, L.C. [Member]
Organization And Basis Of Presentation [Line Items]
Aggregate fee payable | $	$ 937,500
Number of installments of fee payment | Installment	15
Aggregate fee payable, frequency of periodic payment		quarterly
Fee payable in installments | $	$ 62,500
Class A [Member]
Organization And Basis Of Presentation [Line Items]
Common stock, shares authorized | shares		59,779,750	59,779,750		11,038,071
Class A [Member] | Master Transfer Agreement [Member] | CDS [Member]
Organization And Basis Of Presentation [Line Items]
Shares issued | shares	3,100,000
Class A [Member] | Master Transfer Agreement [Member] | FR54, LC [Member]
Organization And Basis Of Presentation [Line Items]
Number of shared issued in exchange to related party | shares	723,947
Series C Preferred Stock [Member]
Organization And Basis Of Presentation [Line Items]
Preferred Stock, shares authorized | shares		20,000,000	4,500,000		3,000,000
Series C Preferred Stock [Member] | Master Transfer Agreement [Member] | CDS [Member]
Organization And Basis Of Presentation [Line Items]
Shares issued | shares	1,220,000
Series C Preferred Stock [Member] | Master Transfer Agreement [Member] | FR54, LC [Member]
Organization And Basis Of Presentation [Line Items]
Number of shares transferred by related party | shares	579,158