BORROWING ARRANGEMENTS - Maturities Table (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Less than 1 Year	$ 851,661
1-2 Years	680
2-3 Years	710
3-4 Years	740
4-5 Years	772
Thereafter	1,136
Total	855,699
Other borrowings:
Debt Instrument [Line Items]
Less than 1 Year	23,172
1-2 Years	0
2-3 Years	0
3-4 Years	0
4-5 Years	0
Thereafter	0
Total	23,172
FHLB borrowings:
Debt Instrument [Line Items]
Less than 1 Year	828,489
1-2 Years	680
2-3 Years	710
3-4 Years	740
4-5 Years	772
Thereafter	1,136
Total	$ 832,527