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FAIR VALUE OF FINANCIAL INSTRUMENTS - Fair Value, Assets and Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation (Details) - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |
Beginning balance - January 1 | $ 45 | $ 89
Included in earnings | 122 | 79
Settlements | (27) | (123)
Settlement of pre-existing relationship | (140) | 0
Ending balance - December 31 | 0 | 45
Total gains for the period included in earnings attributable to the change in unrealized gains on assets still held at the reporting date | $ 0 | $ 45

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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlement of Pre-existing Relationship + References No definition available. + Details
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- Definition Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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