MORTGAGE SERVICING RIGHTS - MSR Activity Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value, beginning of period	$ 1,108,937	$ 113,080	$ 544,562	$ 100,895
Purchases	262,960	98,983	683,983	98,983
Sales	(9,065)	(376)	(9,075)	(376)
Changes in valuation inputs or assumptions	79,606	4,621	238,568	32,296
Other changes, including realization of expected cash flows	(21,018)	(13,692)	(36,618)	(29,182)
Fair value, end of period	$ 1,421,420	$ 202,616	$ 1,421,420	$ 202,616