DERIVATIVES (Offsetting of Financial Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities, Total derivatives subject to a master netting arrangement or similar arrangement	$ 1,431,400	$ 546,054
Gross Amounts Offset in the Condensed Consolidated Balance Sheet	10,625	9,406
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	1,420,775	536,648
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged	797,217	504,638
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives subject to a master netting arrangement or similar arrangement	623,558	32,010
Total derivatives not subject to a master netting arrangement or similar arrangement	3,483	360
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged, Total derivatives not subject to a master netting arrangement or similar arrangement	2,800	273
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives not subject to a master netting arrangement or similar arrangement	683	87
Gross Amounts of Recognized Liabilities, Total Derivative Liabilities	1,434,883	546,414
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total Derivative Liabilities	1,424,258	537,008
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged, Total Derivative Liabilities	800,017	504,911
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total Derivatives Liabilities	624,241	32,097
Other derivative activities
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities, Total derivatives subject to a master netting arrangement or similar arrangement	1,342,888	477,717
Gross Amounts Offset in the Condensed Consolidated Balance Sheet	10,625	9,406
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	1,332,263	468,311
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged	708,705	436,301
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives subject to a master netting arrangement or similar arrangement	623,558	32,010
Cash flow hedges
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities, Total derivatives subject to a master netting arrangement or similar arrangement	88,512	68,337
Gross Amounts Offset in the Condensed Consolidated Balance Sheet	0	0
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	88,512	68,337
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged	88,512	68,337
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total derivatives subject to a master netting arrangement or similar arrangement	$ 0	$ 0

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

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

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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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