Debt instrument floor interest rate.

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- Definition

Debt instrument interest rate payable on maturity.

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Debt instrument interest rate payable on monthly basis.

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Debt Instrument Maturity Description

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Debt instrument maturity month year range end.

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Debt instrument maturity month year range start.

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Line of credit extension period.

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- Definition

Number of promissory notes outstanding.

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- Definition

Number Of Secured Loan

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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No definition available.

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Amount of the required periodic payments applied to interest.

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Percentage of principal amount of debt redeemed.

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No definition available.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

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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Date the credit facility terminates, in CCYY-MM-DD format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of the required periodic payment applied to principal.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Debt - Additional Information (Detail)							12 Months Ended
Debt - Additional Information (Detail)	May 18, 2018	Apr. 16, 2018	Jan. 15, 2018	Dec. 31, 2017 USD ($) SecurityLoan	Dec. 29, 2015 USD ($)	Oct. 17, 2014 USD ($)	Dec. 31, 2017 USD ($) Promissory_Notes	Dec. 31, 2016 USD ($)	Mar. 31, 2018 USD ($)	Dec. 18, 2014 USD ($)
Line of Credit Facility [Line Items]
Outstanding secured debt				$ 23,215,000			$ 23,215,000	$ 26,927,000
Outstanding borrowings for loan				14,893,000			$ 14,893,000	$ 15,866,000
Unsecured Seller-financed Promissory Note [Member]
Line of Credit Facility [Line Items]
Interest rate for period							4.56%
Debt instrument, gross				$ 700,000			$ 700,000
Number of unsecured seller-financed promissory notes outstanding \| Promissory_Notes							2
Comstock Development Services [Member]
Line of Credit Facility [Line Items]
Credit facility outstanding						$ 10,000,000
Other Purchasers [Member]
Line of Credit Facility [Line Items]
Credit facility outstanding						6,200,000
Comstock Growth Fund [Member]
Line of Credit Facility [Line Items]
Interest rate				11.90%			11.90%	10.40%
Interest payments							$ 1,500,000	$ 1,600,000
Commercial Paper One [Member] \| Unsecured Seller-financed Promissory Note [Member]
Line of Credit Facility [Line Items]
Interest rate				9.50%			9.50%
Debt instrument, gross				$ 100,000			$ 100,000
Debt instrument maturity date							Feb. 27, 2020
Commercial Paper One [Member] \| Prime Rate [Member] \| Unsecured Seller-financed Promissory Note [Member]
Line of Credit Facility [Line Items]
Debt instrument spread variable rate							5.00%
Commercial Paper Two [Member] \| Unsecured Seller-financed Promissory Note [Member]
Line of Credit Facility [Line Items]
Debt instrument, gross				600,000			$ 600,000
Debt instrument maturity date							Jul. 17, 2022
Commercial Paper Two [Member] \| LIBOR Rate [Member] \| Unsecured Seller-financed Promissory Note [Member]
Line of Credit Facility [Line Items]
Debt instrument spread variable rate							3.00%
Notes Payable, Other Payables [Member] \| Comstock Growth Fund II, L.C. [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity					$ 10,000,000
Credit facility outstanding					$ 5,000,000
Debt instrument, term					2 years
Outstanding borrowings for loan				3,600,000			$ 3,600,000	3,300,000
Line of credit facility additional extension period					1 year
Debt instrument, interest rate					10.00%
Debt instrument, interest payment terms							Interest payments will be accrued and paid in kind monthly for the first year, and then paid current monthly in arrears beginning December 31, 2016
Notes Payable, Other Payables [Member] \| Comstock Growth Fund [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity						$ 20,000,000				$ 25,000,000
Debt instrument, interest rate description							LIBOR
Interest rate floor						10.00%
Debt instrument, term						3 years
Debt instrument, initial principal amount						$ 10,000,000
Loan annual principal repayment, percentage						10.00%
Principal payments to CGF							$ 1,500,000	1,600,000
Notes Payable, Other Payables [Member] \| Comstock Growth Fund [Member] \| LIBOR Rate [Member]
Line of Credit Facility [Line Items]
Debt instrument spread variable rate						9.75%
Construction Loans [Member] \| Subsequent Events [Member]
Line of Credit Facility [Line Items]
Debt instrument maturity date		Apr. 16, 2018	Jan. 15, 2018
Construction Loans [Member] \| Construction Revolvers [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity				24,800,000			24,800,000	26,600,000
Unused construction loan commitments				$ 17,500,000			$ 17,500,000	$ 20,200,000
Debt instrument, interest rate description							Interest rates charged under these facilities include the London Interbank Offered Rate ("LIBOR") and prime rate pricing options, subject to minimum interest rate floors.
Outstanding construction revolving facilities				4.70%			4.70%	4.60%
Outstanding secured debt				$ 7,300,000			$ 7,300,000	$ 6,400,000
Maturity range, start date							2018-01
Maturity range, end date							2019-02
Credit facility outstanding				5,200,000			$ 5,200,000
Debt instrument, gross				7,337,000			7,337,000	6,429,000
Construction Loans [Member] \| Construction Revolvers [Member] \| Due December 2017 [Member] \| Subsequent Events [Member]
Line of Credit Facility [Line Items]
Outstanding secured debt									$ 7,400,000
Development and Acquisition Notes [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity				28,500,000			28,500,000	27,800,000
Outstanding secured debt				11,600,000			$ 11,600,000	16,300,000
Maturity range, start date							2018-01
Maturity range, end date							2019-03
Debt instrument, gross				$ 11,584,000			$ 11,584,000	16,278,000
Development and Acquisition Notes [Member] \| Subsequent Events [Member]
Line of Credit Facility [Line Items]
Debt instrument maturity date	Mar. 15, 2018
Development and Acquisition Notes [Member] \| Minimum [Member] \| LIBOR and Prime Rate Pricing Options [Member]
Line of Credit Facility [Line Items]
Interest rate floor				7.10%			7.10%
Development and Acquisition Notes [Member] \| Maximum [Member] \| LIBOR and Prime Rate Pricing Options [Member]
Line of Credit Facility [Line Items]
Interest rate floor				5.20%			5.20%
Second and Third Mezzanine Notes [Member]
Line of Credit Facility [Line Items]
Outstanding secured debt				$ 1,200,000			$ 1,200,000	1,400,000
Credit facility outstanding				$ 1,100,000			$ 1,100,000
Interest rate				12.00%			12.00%
Interest rate paid on a monthly basis							6.00%
Interest rate accrued and paid on maturity							6.00%
Line of Credit [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 3,000,000			$ 3,000,000	3,000,000
Outstanding secured debt				$ 2,100,000			$ 2,100,000	$ 2,900,000
Interest rate floor				5.00%			5.00%
Interest rate for period							5.00%	5.00%
Debt instrument maturity description							This line of credit is secured by the first priority security interest in the Company's wholly owned subsidiaries in the Washington, D.C., metropolitan area and is used to finance the predevelopment related expenses and deposits for current and future projects. This line of credit bears a variable interest rate tied to one-month LIBOR plus 3.25% per annum, with an interest rate floor of 5.0%.
Line of credit maturity date							Jun. 30, 2018
Debt instrument, gross				$ 2,131,000			$ 2,131,000	$ 2,929,000
Line of Credit [Member] \| LIBOR Rate [Member]
Line of Credit Facility [Line Items]
Debt instrument spread variable rate							3.25%
Unsecured Note [Member]
Line of Credit Facility [Line Items]
Debt instrument, interest rate description							LIBOR plus 2.2%
Interest rate				3.60%			3.60%	2.90%
Debt instrument, gross				$ 600,000			$ 600,000	$ 1,000,000
Debt instrument maturity date							Dec. 28, 2018
Debt instrument, term							10 years
Unsecured Note [Member] \| LIBOR Rate [Member]
Line of Credit Facility [Line Items]
Debt instrument spread variable rate							2.20%
Unsecured Notes Payable To Affiliate [Member] \| Comstock Growth Fund [Member]
Line of Credit Facility [Line Items]
Outstanding borrowings for loan				$ 11,300,000			$ 11,300,000	$ 12,600,000
Secured Other [Member]
Line of Credit Facility [Line Items]
Number of secured loan \| SecurityLoan				1
Debt instrument, gross				$ 1,100,000			$ 1,100,000
Fixed interest rate				6.00%			6.00%
Debt instrument maturity date				Oct. 17, 2022