SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Net Investment in Domestic and International Leveraged Leases (Details) - Domestic and international leveraged leases - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Leveraged Lease [Line Items]
Net rentals receivable	$ 734	$ 1,410
Unearned income	(178)	(622)
Investment in leveraged leases	556	788
Deferred taxes from leveraged leases	(7)	(238)
Net investment in leveraged leases	$ 549	$ 550

Leveraged Lease Line Items.

No definition available.

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- Definition

Leveraged leases net investment in leveraged leases disclosure unearned income.

+ References

No definition available.

+ Details

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- Definition

The net investment in arrangements meeting the criteria to be classified as leveraged excluding deferred taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 50
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121579104&loc=SL77920254-209983

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121568338&loc=d3e45424-112738

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121555262&loc=d3e45152-112736

+ Details

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- Definition

Taxes arising from arrangements meeting the criteria for classification as leveraged leases due to timing differences between accounting and tax income recognition.

+ References

+ Details

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- Definition

The net investment in arrangements meeting the criteria for classification as leveraged leases including deferred taxes.

+ References

+ Details

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- Definition

This element represents leveraged lease rentals receivable, net of that portion of the rental applicable to principal and interest on the nonrecourse debt.

+ References

+ Details

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- Details

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