Income Taxes - Additional Information (Detail) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Net deferred tax asset	$ 17,663,000	$ 16,815,000
Aggregate Federal NOL carryforwards		38,679,000
Federal NOLs subject to an annual limitation		5,961,000
Federal NOLs not subject to an annual limitation		32,718,000
Federal NOLs annual limitation		$ 2,779,000

Net operating loss annual limitation.

No definition available.

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

+ Details

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

+ References

No definition available.

+ Details

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

+ Details

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