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Basis of Presentation - Additional Information (Detail) | 6 Months Ended
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Jun. 30, 2017 | Jun. 30, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract] |  |
Percentage of comparable consolidated amounts | 95.00% | 95.00%

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- Definition Percentage of comparable consolidated amount. + References No definition available. + Details
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- References No definition available. + Details
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