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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 | Dec. 31, 2015
Operating Loss Carryforwards [Line Items] |  |
Alternative Minimum tax credit carryforwards |  | $ 2.1
Internal Revenue Service (IRS) |  |
Operating Loss Carryforwards [Line Items] |  |
NOL carryforward assets and Research and Development (R&D) credit carryforwards |  | $ 11.3
NOL carryforward assets expiration date |  | 2029
R&D credits expiration year |  | 2035
Federal |  |
Operating Loss Carryforwards [Line Items] |  |
Tax examination description | The Company remains subject to examination by Federal, Maine, Massachusetts, and New Hampshire tax authorities for the tax periods ended December 31, 2012; December 31, 2013; and December 31, 2014. |

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