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Long-Term Incentive Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting period of Grants (in years) | 4 years |  |
Payments made in connection with Long-Term Incentive Plan | $ 4,400,000 | $ 6,500,000 | $ 7,000,000
Grant date fair value | 4,200,000.00 | 6,600,000.00 | 7,800,000.00
Unaccrued cost associated with outstanding grants and related DERs | 700,000 | 5,200,000 |
General Partner [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expenses related to Incentive Plan to be reimbursed to general partner | $ 3,400,000 | $ 1,000,000 | $ 9,600,000
Phantom Share Units (PSUs) [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of trading days (in days) | 20 days |  |

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- Definition Amount of expense for incentive rights held by the managing member or general partner, of limited liability company (LLC) or limited partnership (LP). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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