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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Income Taxes Disclosure [Line Items] |  |  |
Increase (Decrease) in valuation allowance | $ (9,200,000) | $ 11,800,000 |
NOL carry forwards, net of limitations | 100,100,000 | 47,100,000 |
Unrecognized tax benefits | 562,000 | 687,000 | $ 811,000
Accrued interest and penalties related to unrecognized tax benefits | 0 | 0 |
Interest and penalties related to uncertain tax benefits | 0 | 0 |
Unrecognized tax benefits may be recognized by the end of 2016 | $ 0 |  |
Income tax examination description | The Company is subject to U.S. federal, state and local income tax examinations by tax authorities for years 2001 through present. Carryforward attributes that were generated in earlier periods remain subject to examination to the extent the year in which they were used or will be used remains open for examination. The tax years which remain subject to examination by tax authorities in Israel, as of December 31, 2016, include years 2013 through the present. |  |
U.S. Federal [Member] |  |  |
Income Taxes Disclosure [Line Items] |  |  |
NOL carryforwards | $ 24,500,000 | 55,500,000 |
NOL carryforwards, expiration date | Dec. 31, 2036 |  |
U.S. State [Member] |  |  |
Income Taxes Disclosure [Line Items] |  |  |
NOL carryforwards | $ 24,300,000 | 55,400,000 |
NOL carryforwards, expiration date | Dec. 31, 2036 |  |
Foreign [Member] |  |  |
Income Taxes Disclosure [Line Items] |  |  |
NOL carryforwards | $ 26,100,000 | $ 25,600,000 |

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- Definition A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319 + 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=65882285&loc=d3e32559-109319 + Details
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- Definition The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319 + Details
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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unrecognized Tax Benefit -URI http://asc.fasb.org/extlink&oid=6527854 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319 + Details
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=75116654&loc=d3e32123-109318 + Details
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