DERIVATIVES (Offsetting of Financial Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets, Total derivatives subject to a master netting arrangement or similar arrangement	$ 1,387,481	$ 553,289
Gross Amounts Offset in the Condensed Consolidated Balance Sheet, Total Derivative Assets	0	435
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	1,387,481	552,854
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Received, Total Derivative Assets	150,772	69,227
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives subject to a master netting arrangement or similar arrangement	1,236,709	483,627
Total derivatives not subject to a master netting arrangement or similar arrangement	16,118	3,042
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Received	0	0
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount	16,118	3,042
Gross Amounts of Recognized Assets, Total Derivative Assets	1,403,599	556,331
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheet, Total Derivative Assets	1,403,599	555,896
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Received, Total Derivative Assets	150,772	69,227
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet - Net Amount, Total Derivative Assets	1,252,827	486,669
Other derivative activities
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets, Total derivatives subject to a master netting arrangement or similar arrangement	1,175,845	524,258
Gross Amounts Offset in the Condensed Consolidated Balance Sheet, Total Derivative Assets	0	435
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	1,175,845	523,823
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Received, Total Derivative Assets	9,705	51,437
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives subject to a master netting arrangement or similar arrangement	1,166,140	472,386
Cash flow hedges
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets, Total derivatives subject to a master netting arrangement or similar arrangement	211,636	29,031
Gross Amounts Offset in the Condensed Consolidated Balance Sheet, Total Derivative Assets	0	0
Net Amounts of Assets Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	211,636	29,031
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Received, Total Derivative Assets	141,067	17,790
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives subject to a master netting arrangement or similar arrangement	$ 70,569	$ 11,241

Derivative Asset, Collateral, Right To Reclaim Cash, Including Not Subject To Master Netting Arrangement

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Derivative Asset, Not Subject To Master Netting Arrangement, Collateral, Right To Reclaim Cash

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Derivative Asset, Offset Against Collateral, Not Subject To Master Netting Arrangement

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against an obligation to return collateral.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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