DERIVATIVES (Offsetting of Financial Liabilities) (Details) - USD ($) $ in Thousands	Sep. 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	$ 1,220,077	$ 546,054
Gross Amounts Offset in the Condensed Consolidated Balance Sheet	3,861	9,406
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	1,216,216	536,648
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged	738,444	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	477,772	32,010
Total derivatives not subject to a master netting arrangement or similar arrangement	308	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	106	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	202	87
Gross Amounts of Recognized Liabilities, Total Derivative Liabilities	1,220,385	546,414
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total Derivative Liabilities	1,216,524	537,008
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged, Total Derivative Liabilities	738,550	504,911
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Net Amount, Total Derivatives Liabilities	477,974	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	1,140,477	477,717
Gross Amounts Offset in the Condensed Consolidated Balance Sheet	3,861	9,406
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet, Total derivatives subject to a master netting arrangement or similar arrangement	1,136,616	468,311
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged	659,094	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	477,522	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	79,600	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	79,600	68,337
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Collateral Pledged	79,350	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	$ 250	$ 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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