Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Description of debt redemption features under terms of the debt agreement.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of cash inflow from issuance of long-term debt classified as other.

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DEBT Narrative 1 (Details) - USD ($) $ in Thousands		9 Months Ended
DEBT Narrative 1 (Details) - USD ($) $ in Thousands	Sep. 14, 2020	Sep. 30, 2020	Sep. 30, 2019	Aug. 31, 2020
Debt Instrument [Line Items]
Proceeds from note offerings, net of issuance costs	$ 1,183,900	$ 1,183,942	$ 491,588
Long-term debt, issuance costs	$ 16,100
Logistics Notes due 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, rate	5.75%
Long-term debt	$ 600,000
Debt instrument, redemption, description		At the option of NuStar Logistics, the 5.75% and 6.375% senior notes may be redeemed in whole or in part at any time at a redemption price, plus accrued and unpaid interest to the redemption date. If we undergo a change of control, as defined in the supplemental indenture for the 5.75% and 6.375% senior notes, each holder of the notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.
Logistics Notes due 2030 [Member]
Debt Instrument [Line Items]
Long-term debt, rate	6.375%
Long-term debt	$ 600,000
Debt instrument, redemption, description		At the option of NuStar Logistics, the 5.75% and 6.375% senior notes may be redeemed in whole or in part at any time at a redemption price, plus accrued and unpaid interest to the redemption date. If we undergo a change of control, as defined in the supplemental indenture for the 5.75% and 6.375% senior notes, each holder of the notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.
Logistics Notes due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, rate				4.80%
Long-term debt				$ 450,000