FAIR VALUE (Activity for Assets and Liabilities Measured on Recurring Level 3 Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
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	$ 28,301	$ 21,875
Net unrealized gains (losses) arising during the period	1,244	5,620
ASU 2017-08
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption	(300)
Investments in Debt Securities
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	28,300
Net unrealized gains (losses) arising during the period	1,200
Loans Held for Investment
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at end of period	500
Level 3 [Member] \| Derivative Liabilities [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning period		(46)
Net (losses) gains included in earnings		(41)
Impact from settlements		87
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	97,190	143,604
Net (losses) gain included in earnings		(6)
Net change in AOCI (1)	(27,057)	(16,249)
Impact from deconsolidation		17,998
Impacts from sales/redemptions	(38,209)	(47,488)
Impacts from settlements	(559)	(669)
Balance at end of period	31,365	97,190
Reclassification of net fair value gains on sold/redeemed bonds		21,900
Level 3 [Member] \| Loans Held for Investment
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Impact from originations	500
Balance at end of period	500
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	2,347
Net (losses) gains included in earnings	(195)	854
Impact from settlements	$ (935)	(2,071)
Balance at ending period		$ 1,130

Fair Value, Measurement with Unobservable Inputs Reconciliation, Increase (Decrease) from Deconsolidation

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3).

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Amount of settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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