Income Taxes - Reconciliation of Statutory Federal Income Tax Rate to the Company's Effective Tax Rate (Detail)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Expected income tax provision at the federal statutory rate	34.00%	34.00%
State taxes, net of federal benefit	4.70%	4.50%
Change in valuation allowance	(37.80%)	(36.80%)
Nondeductible expenses	(0.90%)	(1.80%)
Withholding taxes	(0.10%)	(0.10%)
Income tax provision	(0.10%)	(0.20%)

Effective income tax rate reconciliation withholding taxes.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
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-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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-Publisher FASB
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 740
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

+ References

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