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Total change in each class of partners' capital accounts during the year due to exchanges and conversions. Partners include general, limited and preferred partners.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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The number of units converted into shares of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 16

-Subparagraph a, b

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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Distribution made to member or limited partner distribution period.

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General partner marginal interest in distributions.

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Partners’ capital account units converted, description.

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Partnership Distributions - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended
	Aug. 15, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Limited Partners Capital Account [Line Items]
Partnership cash distribution period		45 days
Partnership cash distribution paid		$ 536,716us-gaap_PaymentsOfDividends	$ 389,128us-gaap_PaymentsOfDividends	$ 251,720us-gaap_PaymentsOfDividends
Conversion of subordinated units to common units	69,076,122
General partnership interest and distribution right		2.00%
Maximum
Limited Partners Capital Account [Line Items]
General partnership interest and distribution right		50.00%
Class B Units
Limited Partners Capital Account [Line Items]
Beneficial conversion feature				$ 58,300
Subordinated units
Limited Partners Capital Account [Line Items]
Units converted into common units, basis description		one-for-one
Class C Units
Limited Partners Capital Account [Line Items]
Units converted into common units, basis description		one-for-one