GUARANTEES (Details) $ in Millions	Sep. 30, 2021 USD ($)
Guarantees
Total guarantees	$ 276.2
Guarantees expiring in less than 1 year	118.6
Guarantees expiring within 1 to 3 years	1.5
Guarantees with expiration over 3 years	156.1
Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	125.5
Guarantees expiring in less than 1 year	51.5
Guarantees expiring within 1 to 3 years	1.5
Guarantees with expiration over 3 years	72.5
Standby letters of credit
Guarantees
Total guarantees	127.2
Guarantees expiring in less than 1 year	54.3
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	72.9
Surety bonds
Guarantees
Total guarantees	12.8
Guarantees expiring in less than 1 year	12.8
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	0.0
Other guarantees
Guarantees
Total guarantees	10.7
Guarantees expiring in less than 1 year	0.0
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	10.7
Other indemnifications
Guarantees
Liability related to workers compensation coverage	10.7
UMERC | Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	4.2
Bluewater | Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	8.1
WECI | Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	$ 113.2