v2.4.0.8

EMPLOYEE BENEFIT PLANS AND LONG-TERM INCENTIVE PLANS Narrative (Details) (USD $) In Millions, except Share data, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Benefit Plan Costs, International Employees | $ 2.5 | $ 2.6 | $ 2.6
General partner employees benefit plans |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Pension Plan, Description | The NuStar Pension Plan (the Pension Plan) is a qualified non-contributory defined benefit pension plan that became effective July 1, 2006. The Pension Plan covers substantially all of NuStar GP, LLC’s employees and generally provides eligible employees with retirement income calculated under a final average pay formula (FAP) or a cash balance formula. Employees hired before January 1, 2011 are covered under FAP, which is based on years of service and compensation during their period of service, and employees become fully vested in their benefits upon attaining five years of vesting service. Employees hired on January 1, 2011 or after are covered under the cash balance formula, which is based on age and service and interest credits, and employees become fully vested in their benefits upon attaining three years of vesting service. Effective January 1, 2014, the Pension Plan was amended to freeze the FAP benefit as of December 31, 2013 and all employees will be covered under the cash balance formula. |  |
Thrift Plan, Description | The NuStar Thrift Plan (the Thrift Plan) is a qualified employee profit-sharing plan that became effective June 26, 2006. Participation in the Thrift Plan is voluntary and is open to substantially all NuStar GP, LLC employees upon their date of hire, except for part-time employees (as defined in the Thrift Plan), who become eligible upon completing one year of service (as defined in the Thrift Plan). Thrift Plan participants can contribute from 1% up to 30% of their total annual compensation to the Thrift Plan in the form of pre-tax and/or after tax employee contributions. NuStar GP, LLC makes matching contributions in an amount equal to 100% of each participant’s employee contributions up to a maximum of 6% of the participant’s total annual compensation. |  |
General partner employees benefit plans | The 2000 LTIP [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unit-based compensation, number of units authorized | 3,250,000 |  |
Unit-based compensation, number of units available to be awarded | 1,517,027 |  |
General partner employees benefit plans | The 2006 LTIP [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unit-based compensation, number of units authorized | 2,000,000 |  |
Unit-based compensation, number of units available to be awarded | 1,494,177 |  |

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- Definition Costs for defined contribution plans for certain international employees. + References No definition available. + Details
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- Definition Non-contributory Defined Benefit Pension Plan, Description of terms and benefits + References No definition available. + Details
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- Definition Description of the terms and benefits provided by the employer's defined contribution plans. A defined contribution plan provides benefits in return for services rendered, provides an individual account for each participant, and has terms that specify how contributions to the individual's account are to be determined rather than the amount of benefits the individual is to receive. Under a defined contribution pension plan, the benefits a participant will receive depend solely on the amount contributed to the participant's account, the returns earned on investments of those contributions, and forfeitures of other participants' benefits that may be allocated to such participant's account. A description of the plan(s) including employee groups covered, the basis for determining contributions, and the nature and effects of significant matters affecting comparability of information for all periods presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Defined Contribution Postretirement Plan -URI http://asc.fasb.org/extlink&oid=6510416 + Details
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- Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + 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)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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