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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified |  | 12 Months Ended | 9 Months Ended |  | 12 Months Ended
--- | --- | --- | --- | --- | ---
Dec. 31, 2013 | Dec. 31, 2013 Internal Revenue Service (IRS) | Sep. 30, 2014 Federal | Dec. 31, 2013 Federal and State | Dec. 31, 2013 State and Local Jurisdiction
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Net Operating Loss carryforward assets |  | $ 2.1 |  | $ 19.0 |
NOL carryforward assets expiration date |  | 2029 |  |  | 2019
Alternative Minimum tax credit carryforwards | $ 2.1 |  |  |  |
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, 2011; December 31, 2012; and December 31, 2013. |  |

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