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Business and Organization (Detail) | 9 Months Ended | 12 Months Ended
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Sep. 30, 2017 Segment Acquisition | Dec. 31, 2016 Acquisition
Organization And Description Of Business [Line Items] |  |
Number of reportable segments | Segment | 2 |
Acquisitions 2017, other than Stronghold |  |
Organization And Description Of Business [Line Items] |  |
Number of business acquisitions | 2 |
Acquisitions 2016 |  |
Organization And Description Of Business [Line Items] |  |
Number of business acquisitions |  | 5

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- Definition The number of businesses acquired by the entity during the period. + References No definition available. + Details
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
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- Details
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- Details
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