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FAIR VALUE (Activity for Assets and Liabilities Measured on Recurring Level 3 Basis) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2019
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Reclassification of net fair value gains on sold/redeemed bonds	$ 0	$ 3,571
Net unrealized gains (losses) arising during the period	(1,763)	406
Investments in Debt Securities
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Net unrealized gains (losses) arising during the period	1,800
Loans Held for Investment
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at start of period	500
Balance at end of period	1,271
Level 3 [Member] \| Investments in Debt Securities
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at start of period	31,365	97,190
Net change in AOCI (1)	(1,763)	(3,165)
Impacts from sales/redemptions		(12,590)
Impacts from settlements	43	(333)
Balance at end of period	29,645	81,102
Reclassification of net fair value gains on sold/redeemed bonds		3,600
Level 3 [Member] \| Loans Held for Investment
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at start of period	500
Net (losses) gain included in earnings	(9)
Impact from loan originations / advances	780
Balance at end of period	$ 1,271
Level 3 [Member] \| Derivative Assets [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning period		1,130
Net (losses) gains included in earnings		(152)
Impact from settlements		(202)
Balance at ending period		$ 776
Restatement Adjustment [Member] \| ASU 2017-08
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Retained earnings			$ (300)