EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended						6 Months Ended
	May 31, 2026	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026
Class of Stock [Line Items]
Quarterly dividend on all classes of common stock (in dollars per share)		$ 1.60	$ 1.60	$ 1.50	$ 1.50	$ 1.50	$ 1.50
Repurchase of Class C Common Stock (in shares)								47,319
Repurchase of Class C Common Stock			$ 7,178
Remaining authorized amount for repurchase		$ 30,000						$ 30,000
Capital required for capital adequacy		1,100,000		$ 1,000,000				1,100,000
Capital		1,900,000		1,700,000				1,900,000
Excess capital		$ 730,700		$ 677,700				730,700
Class C non-voting common stock
Class of Stock [Line Items]
Repurchase of Class C Common Stock								$ 7,100
Series I
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)	4,000,000.0	4,000,000		4,000,000				4,000,000
Preferred stock, dividend rate	6.875%
Preferred stock, par value (in dollars per share)	$ 25.00	$ 25		$ 25				$ 25
Payments of stock issuance costs	$ 3,200