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Quarterly Results of Operations - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
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Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Pre-tax income related to insurance recoveries |  |  |  |  | $ 200 | $ 100 | $ 300 | $ 3,100 | $ 443 | $ 3,657 | $ 10,368
Adjustment to the reserve for uncertain tax positions, net |  |  |  |  |  |  |  | $ 3,000 |  |  |
Basic and diluted net income (loss) per share | $ 0.20 | $ 0.15 | $ 0.02 | $ (0.05) | $ (0.11) | $ 0.02 | $ (0.60) | $ 0.21 | $ 0.31 | $ (0.49) | $ 0.59
Workforce Reduction Charges |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basic and diluted net income (loss) per share |  |  |  |  |  |  | (0.07) |  |  |  |
Other-Than-Temporary Impairment Charge in Marketable Equity Security |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basic and diluted net income (loss) per share |  |  |  |  |  | $ (0.03) |  |  |  |  |
Insurance Settlement Gains |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basic and diluted net income (loss) per share |  |  |  | $ 0.01 |  |  |  |  |  |  |
Execution and Finalization of Agreement | US-Canada APA |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basic and diluted net income (loss) per share | (0.01) | $ 0.02 |  |  |  |  |  |  |  |  |
Increase (Decrease) in Uncertain Tax Positions |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basic and diluted net income (loss) per share | (0.01) |  |  |  |  |  |  |  |  |  |
Deferred Income Tax Asset Valuation Allowance |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basic and diluted net income (loss) per share | $ 0.02 |  | $ (0.01) |  |  |  | $ (0.65) |  |  |  |

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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References No definition available. + Details
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- Definition The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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