SUBSEQUENT EVENT (Details) - Unsecured Term Loan Credit Agreement [Member] - Subsequent Event [Member] $ in Millions	Apr. 21, 2020 USD ($)
Subsequent Event [Line Items]
The Term Loan, Initial Loan	$ 500.0
Debt Instrument, Unused Borrowing Capacity, Amount	$ 250.0
Long-term debt, term	3 years
Long-term debt, aggregate commitment amount available	$ 750.0
Long-term debt, additional aggregate principal amount available, terms	NuStar Logistics may elect to draw, on or prior to April 19, 2021, in one or more draws, subject to certain conditions.
Long-term debt, rate	12.00%
Long-term debt, original issue discount, percent	3.00%
Long-term debt, commitment fee, percent	5.00%
Debt Instrument, Payment Terms	NuStar Logistics is required to make mandatory prepayment in an amount equal to 100.0% of the proceeds received as a result of certain events, subject to certain exclusions and adjustments, such as the incurrence of additional indebtedness (excluding additional borrowings under the Revolving Credit Agreement), the issuance of equity securities and the sale of property or assets. Depending on the amount of time that has passed since the Initial Loan Funding Date, if there is a payment or prepayment (subject to certain exceptions), NuStar Logistics is required to pay, as liquidated damages and compensation for the costs of making funds available, a make-whole premium or similar amount. From the Initial Loan Funding Date through the 18-month anniversary of the Initial Loan Funding Date, such premium will be the sum of (i) the make-whole amount and (ii) 6.25% of the aggregate principal amount of borrowings then paid, prepaid or accelerated. After the 18-month anniversary of the Initial Loan Funding Date through the 30-month anniversary of the Initial Loan Funding Date, such premium will be 6.25% of the aggregate principal amount of borrowings then paid, prepaid or accelerated. Prepayments made in connection with one or more asset sales of up to an aggregate amount of $250.0 million will be subject to a lower prepayment premium. For asset sale prepayments from the Initial Loan Funding Date through the 18-month anniversary of the Initial Loan Funding Date, such premium will be 5.0% of the aggregate principal amount of borrowings then paid, prepaid or accelerated. After the 18-month anniversary of the Initial Loan Funding Date through the 30-month anniversary of the Initial Loan Funding Date, such premium will be 3.0% of the aggregate principal amount of borrowings then paid, prepaid or accelerated. There will be no premium for any prepayments of borrowings after the 30-month anniversary of the Initial Loan Funding Date.

Original Issue Discount

No definition available.

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- Definition

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

+ References

+ Details

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- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

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- Definition

Description of unused borrowing capacity under the debt instrument and conditions under which the commitment can be withdrawn by the lender.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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