Consolidated Statements Of Partners' Capital (USD $) In Thousands, except Share data	Total	Number Of Common Units [Member]
Partners' capital, value at Dec. 31, 2011	$ 792,638us-gaap_LimitedPartnersCapitalAccount
Partners' capital, shares at Dec. 31, 2011		71,965,000
Net income (loss)	96,319us-gaap_ProfitLoss	0
Cash distributions	(142,383)	0
Issuance of units for cash, shares		5,750,000
Partners' Capital Account, Sale of Units	169,421
Partners' Capital Account, Units, Converted		3,476,000
Partners' Capital Account, Exchanges and Conversions	0
Partners' capital, Other	500us-gaap_PartnersCapitalOther	12
Partners' capital, value at Dec. 31, 2012	916,495us-gaap_LimitedPartnersCapitalAccount
Partners' capital, shares at Dec. 31, 2012		81,203,000
Net income (loss)	86,109us-gaap_ProfitLoss	0
Cash distributions	(168,441)	0
Issuance of units for cash, shares		5,750,000
Partners' Capital Account, Sale of Units	263,574
Partners' Capital Account, Units, Converted		1,738,000
Partners' Capital Account, Exchanges and Conversions	0
Partners' capital, value at Dec. 31, 2013	1,097,737us-gaap_LimitedPartnersCapitalAccount
Partners' capital, shares at Dec. 31, 2013	88,690,985	88,691,000
Net income (loss)	106,202us-gaap_ProfitLoss	0
Cash distributions	(200,461)	0
Issuance of units for cash, shares		4,600,000
Partners' Capital Account, Sale of Units	225,725
Partners' Capital Account, Units, Converted		1,738,000
Partners' Capital Account, Exchanges and Conversions	0
Partners' capital, value at Dec. 31, 2014	$ 1,229,203us-gaap_LimitedPartnersCapitalAccount
Partners' capital, shares at Dec. 31, 2014	95,029,218	95,029,000

The amount of the limited partners' ownership interests.

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

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-Name Accounting Standards Codification

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The number of limited partner units outstanding.

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

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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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Total change in each class of partners' capital accounts during the year due to the sale of units. All partners include general, limited and preferred partners.

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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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Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.

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This element represents movements included in the statement of changes in partners' capital which are not separately disclosed or provided for elsewhere in the taxonomy.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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