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Acquisitions - Business Acquisition Pro Forma Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013
Business Combinations [Abstract] |  |
Total revenues and other income | $ 533,517 | $ 579,933
Net income | $ 122,319 | $ 197,164
Basic and diluted net income per common unit | $ 9.90 | $ 16.00

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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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