EQUITY (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024
Equity [Abstract]
Quarterly dividend on all classes of common stock (in dollars per share)	$ 1.50	$ 1.50	$ 1.40	$ 1.40	$ 1.40	$ 1.40
Capital required for capital adequacy	$ 959.9		$ 917.6
Capital	1,600.0		1,500.0
Excess capital	$ 602.1		$ 583.5

Amount of total capital as defined by regulatory framework.

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- Definition

Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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- References

No definition available.

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- Definition

Amount of total risk-based capital exceeding minimum required for capital adequacy as defined by regulatory framework.

+ References

+ Details

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