DERIVATIVES - Derivatives Recorded at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative assets	$ 255,496	$ 41,501
Derivative liabilities	37,820	6,885
Interest rate swaps
Derivative [Line Items]
Derivative assets	0	155
Derivative liabilities	263	0
Derivative asset, variation margin accounts	206,300	171,800
Interest rate lock commitments
Derivative [Line Items]
Derivative assets	246,247	41,346
Derivative liabilities	283	1,455
Forward loan sale commitments
Derivative [Line Items]
Derivative liabilities	0	27
TBAs
Derivative [Line Items]
Derivative assets	9,249	0
Derivative liabilities	$ 37,274	$ 5,403

Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant