MORTGAGE SERVICING RIGHTS - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Bank Servicing
Servicing Assets at Fair Value [Line Items]
Service income fee	$ 56,800,000	$ 66,600,000
Interests in MSR
Servicing Assets at Fair Value [Line Items]
Service income fee	$ 7,600,000	$ 0