Income Taxes - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($)
Income Taxes And Tax Related [Line Items]
Statutory federal income tax rate	34.00%
Federal and State [Member]
Income Taxes And Tax Related [Line Items]
Net operating loss carryforwards	$ 165.4
Tax credit carryforwards	$ 4.2
Earliest Tax Year [Member]
Income Taxes And Tax Related [Line Items]
Operating loss carryforwards expiration year	2025
Open for examination	2004
Latest Tax Year [Member]
Income Taxes And Tax Related [Line Items]
Operating loss carryforwards expiration year	2036

Income Taxes And Tax Related [Line Items]

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Net Operating Loss Carry Forwards Expiration Year

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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
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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-Section S99
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-Section 50
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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit 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
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