SECURITIES - Securities by Remaining Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Within 1 year	$ 137,266	$ 379,700
1-5 years	348,038	207,590
5-10 years	105	130
After 10 years	0	0
Total	485,409	587,420
Equity securities	100	100
Allowance for current expected credit losses	(20)	(20)
CMBS
Debt Securities, Available-for-sale [Line Items]
Within 1 year	81,343	346,272
1-5 years	343,547	195,061
5-10 years	0	0
After 10 years	0	0
Total	424,890	541,333
CMBS interest-only
Debt Securities, Available-for-sale [Line Items]
Within 1 year	2,121	937
1-5 years	4,448	9,506
5-10 years	0	0
After 10 years	0	0
Total	6,569	10,443
GNMA interest-only
Debt Securities, Available-for-sale [Line Items]
Within 1 year	86	40
1-5 years	22	111
5-10 years	105	130
After 10 years	0	0
Total	213	281
Agency securities
Debt Securities, Available-for-sale [Line Items]
Within 1 year	0	0
1-5 years	21	35
5-10 years	0	0
After 10 years	0	0
Total	21	35
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Within 1 year	53,716	32,451
1-5 years	0	2,877
5-10 years	0	0
After 10 years	0	0
Total	$ 53,716	$ 35,328