DERIVATIVE FINANCIAL INSTRUMENTS - Interest Rate Futures Positions (Details) - Short [Member] - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Repurchase Agreement Funding Hedges [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	$ 100,000,000	$ 125,000,000
Entry Rate	2.86%	2.74%
Weighted Average Effective Rate	1.63%	2.54%
Open Equity	$ (2,464,000)	$ (730,000)
Repurchase Agreement Funding Hedges [Member] | Year 2019 Expiration [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount		$ 125,000,000
Entry Rate		2.56%
Weighted Average Effective Rate		2.67%
Open Equity		$ 139,000
Repurchase Agreement Funding Hedges [Member] | Year 2020 Expiration [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	$ 120,000,000	$ 150,000,000
Entry Rate	2.90%	2.84%
Weighted Average Effective Rate	1.67%	2.49%
Open Equity	$ (1,480,000)	$ (523,000)
Repurchase Agreement Funding Hedges [Member] | Year 2020 Expiration [Member] | Treasury Note Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	$ 20,000,000
Entry Rate	1.96%
Weighted Average Effective Rate	2.06%
Open Equity	$ 88,000
Repurchase Agreement Funding Hedges [Member] | Year 2021 Expiration [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	$ 80,000,000	$ 100,000,000
Entry Rate	2.80%	2.80%
Weighted Average Effective Rate	1.57%	2.46%
Open Equity	$ (984,000)	$ (346,000)
Junior Subordinated Debt Funding Hedges [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	$ 19,500,000	$ 26,000,000
Entry Rate	1.92%	1.93%
Weighted Average Effective Rate	1.68%	2.54%
Open Equity	$ (46,000)	$ 474,000
Junior Subordinated Debt Funding Hedges [Member] | Year 2019 Expiration [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount		$ 26,000,000
Entry Rate		1.63%
Weighted Average Effective Rate		2.68%
Open Equity		$ 271,000
Junior Subordinated Debt Funding Hedges [Member] | Year 2020 Expiration [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	$ 19,500,000	$ 26,000,000
Entry Rate	1.92%	1.95%
Weighted Average Effective Rate	1.68%	2.49%
Open Equity	$ (46,000)	$ 142,000
Junior Subordinated Debt Funding Hedges [Member] | Year 2021 Expiration [Member] | Eurodollar Future [Member]
Derivatives, Fair Value [Line Items]
Notional Amount		$ 26,000,000
Entry Rate		2.22%
Weighted Average Effective Rate		2.46%
Open Equity		$ 61,000