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Description of the Business and Basis of Presentation (Detail) |  |  | 12 Months Ended
--- | --- | --- | ---
Oct. 31, 2012 | Mar. 27, 2012 | Dec. 31, 2018
Description Of Business And Basis Of Presentation [Line Items] |  |  |
Date of partnership formation |  | Mar. 27, 2012 |
Date for initial public offering completed | Oct. 31, 2012 |  |
Number of reportable segments |  |  | 2

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- Definition Description Of Business And Basis Of Presentation [Line Items] + References No definition available. + Details
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- Definition Initial Public Offering Completion Date + References No definition available. + Details
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- Definition Date the limited liability company (LLC) or limited partnership (LP) was formed, in CCYY-MM-DD format. + 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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