MORTGAGE SERVICING RIGHTS - MSR Activity Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning of period	$ 1,790,980	$ 1,108,937	$ 1,748,209	$ 544,562
Purchases	177,521	262,960	214,151	683,983
Sales	0	(9,065)	0	(9,075)
Changes in valuation inputs or assumptions	80,323	79,606	110,530	238,568
Other changes, including realization of expected cash flows	(29,928)	(21,018)	(53,994)	(36,618)
Fair value, end of period	$ 2,018,896	$ 1,421,420	$ 2,018,896	$ 1,421,420