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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Taxes [Line Items] |  |  |
Tax computed at federal rate, percentage | 21.00% | 21.00% | 35.00%
Tax Cuts and Jobs Act of 2017, completed accounting, income tax expense | $ 0 | $ 0 | $ 11,644,000
State and Canadian net operating losses (NOLs) | $ 14,000,000.0 | 9,400,000 |
State and Canadian net operating losses (NOLs), expiration year | 2033 |  |
Valuation allowance, deferred tax assets | $ 3,900,000 | 2,600,000 |
Change in valuation allowance, deferred tax assets | 1,400,000 | 677,000 | $ 170,000
Decrease in unrecognized tax benefits that is reasonably possible | 701,000 |  |
Unrecognized tax benefits related to penalties | $ 136,000 | 167,000 |
Income Tax Examination, Description | The Company is not currently under income tax examination by any taxing authority. |  |
Undistributed earnings of foreign subsidiary | $ 0 | $ 0 |
Minimum [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax years subject to tax examinations | 2015 |  |
Maximum [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax years subject to tax examinations | 2019 |  |

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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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- Definition Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to Tax Cuts and Jobs Act. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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