Notes Payable, net - Outstanding Notes Payable (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 18,520,000	$ 14,313,750
Less unamortized deferred loan costs	(202,638)	(227,420)
Long-term Debt, Total	18,317,362	14,086,330
Mortgage Agreement, Collateralized By Village Pointe SC Property \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	3,525,000
Mortgage Agreement, Collateralized By Village Pointe SC Property \| Mortgages \| LIBOR
Debt Instrument [Line Items]
Rate	2.75%
Mortgage Agreement Collateralized By Richardson Tech Center Property \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,520,000	2,520,000
Interest rate	4.55%
Mortgage Agreement Collateralized By Richardson Tech Center Property \| Mortgages \| LIBOR
Debt Instrument [Line Items]
Rate	2.75%
East West Bank Master Credit Facility Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 20,000,000
Interest rate	4.25%
Line of credit facility, remaining borrowing capacity	$ 4,000,000
East West Bank Master Credit Facility Agreement \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 16,000,000	$ 8,268,750
East West Bank Master Credit Facility Agreement \| Line of Credit \| Revolving Credit Facility \| Prime Rate
Debt Instrument [Line Items]
Rate	(0.50%)

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

No definition available.

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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.

+ References

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- Definition

The average effective interest rate during the reporting period.

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- Definition

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

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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.

+ References

No definition available.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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