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Commitments and Contingencies - Additional Information (Detail) - USD ($) |  |  | 12 Months Ended
--- | --- | --- | ---
Dec. 09, 2014 | Dec. 07, 2012 | Dec. 31, 2015
December 7, 2012 Agreement [Member] |  |  |
Commitment And Contingencies [Line Items] |  |  |
Commitment towards investments in joint venture |  | $ 1,200,000 |
Contribution to joint venture |  | $ 850,000 |
December 9, 2014 Agreement [Member] |  |  |
Commitment And Contingencies [Line Items] |  |  |
Contribution to joint venture |  |  | $ 1.0
December 9, 2014 Agreement [Member] | Maximum [Member] |  |  |
Commitment And Contingencies [Line Items] |  |  |
Commitment towards investments in joint venture | $ 1,000,000 |  |

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- Definition Commitment And Contingencies [Line Items] + References No definition available. + Details
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