Redeemable preferred stock outstanding.

No definition available.

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- Definition

Short-term investments maturity period.

+ References

No definition available.

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- Definition

The amount of asset retirement costs previously incurred and capitalized separately from the capitalized amount of the associated long-lived assets.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
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- Definition

Decrease for amounts of indebtedness forgiven by the holder of the debt instrument.

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- Definition

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Topic 842
-SubTopic 30
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- Definition

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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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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Organization and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 29, 2016
Property, Plant and Equipment [Line Items]
Short-term investment maturity period		3 months
Restricted cash		$ 10,135	$ 10,010
Reverse stock split ratio		1-for-12
Capitalized cost of assets held for sale	$ 416,329	$ 4,600,000
Decrease in indebtedness	$ 650,000
Weighted average number of common shares outstanding		8,583,795	8,209,539	7,564,082
Redeemable preferred stock outstanding		0
Minimum [Member]
Property, Plant and Equipment [Line Items]
Lease term					12 months
Property and Equipment, estimated useful life		3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, estimated useful life		30 years