Acquisitions - Business Acquisition Pro Forma Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
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

Business Acquisition Pro Forma Earnings Per Share Basic And Diluted

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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

+ Details

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- References

No definition available.

+ Details

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