MORTGAGE SERVICING RIGHTS - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Servicing Assets at Fair Value [Line Items]
Mortgage Servicing Rights Held-For-Sale	$ 86,200,000		$ 86,200,000		$ 0
Bank Servicing
Servicing Assets at Fair Value [Line Items]
Service income fee	14,900,000	$ 15,100,000	29,700,000	$ 54,400,000
Interest in MSRs
Servicing Assets at Fair Value [Line Items]
Service income fee	$ 2,700,000	$ 0	$ 4,700,000	$ 0