GUARANTEES (Details) $ in Millions	Mar. 31, 2021 USD ($)
Guarantees
Total guarantees	$ 234.2
Guarantees expiring in less than 1 year	70.9
Guarantees expiring within 1 to 3 years	1.6
Guarantees with expiration over 3 years	161.7
Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	138.5
Guarantees expiring in less than 1 year	53.5
Guarantees expiring within 1 to 3 years	1.5
Guarantees with expiration over 3 years	83.5
Standby letters of credit
Guarantees
Total guarantees	73.3
Guarantees expiring in less than 1 year	5.1
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	68.2
Surety bonds
Guarantees
Total guarantees	12.4
Guarantees expiring in less than 1 year	12.3
Guarantees expiring within 1 to 3 years	0.1
Guarantees with expiration over 3 years	0.0
Other guarantees
Guarantees
Total guarantees	10.0
Guarantees expiring in less than 1 year	0.0
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	10.0
Other indemnifications
Guarantees
Liability related to workers compensation coverage	10.0
UMERC \| Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	4.2
Bluewater \| Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	8.2
WECI \| Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	$ 126.1

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

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- Definition

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.

+ References

No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

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- Definition

Represents the maximum potential payments with respect to the entity's guarantees that expire in less than a year.

+ References

No definition available.

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- Definition

Represents the maximum potential payments with respect to the entity's guarantees that expire after three years.

+ References

No definition available.

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- Definition

Represents the maximum potential payments with respect to the entity's guarantees that expire within one to three years.

+ References

No definition available.

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