EQUITY (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended					49 Months Ended
	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Mar. 31, 2025	Feb. 28, 2023
Class of Stock [Line Items]
Quarterly dividend on all classes of common stock (in dollars per share)	$ 1.50	$ 1.40	$ 1.40	$ 1.40	$ 1.40
Capital required for capital adequacy	$ 926.7	$ 917.6				$ 926.7
Capital	1,500.0	1,500.0				1,500.0
Excess capital	$ 600.8	$ 583.5				$ 600.8
Class C non-voting common stock
Class of Stock [Line Items]
Remaining authorized amount for repurchase							$ 9.8
Shares repurchased (in shares)						0