Leases (Lessor: Summary of Sales-Type, Direct Financing, Operating and Leveraged Leases) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Net Interest Income and Other Financing Income
Sales-Type and Direct Financing	$ 33
Operating Lease, Lease Income	11
Leveraged Leases, Income Loss	14
Lease Income	58
Sales-Type and Direct Financing [Abstract]
Sales-type and direct financing lease receivable	1,068
Sales-type and direct financing, unearned income.	(215)
Sales type and direct financing lease Guaranteed residual	32
Sales Type and Direct Financing Unguaranteed residual	152
Total net investment	1,037
Operating [Abstract]
Operating	113
Unearned Income	(29)
Guaranteed residual	0
Unguaranteed residual	213
Total net investment	297
Leveraged
Lease Receivable	182
Unearned Income	(113)
Guaranteed residual	0
Unguaranteed residual	147
Total net investment	216
Total
Lease Receivable	1,363
Unearned Income	(357)
Guaranteed residual	32
Unguaranteed residual	512
Total net investment	$ 1,550

Lessor, Operating Lease, Net Investment

No definition available.

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Lessor, Operating Lease, Unearned Income

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No definition available.

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Leveraged Leases, Net Investment in Leveraged Leases Disclosure, Guaranteed Residual Value of Leased Assets

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No definition available.

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Leveraged Leases, Net Investment in Leveraged Leases Disclosure, Unguaranteed Residual Value of Leased Assets

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No definition available.

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Operating [Abstract]

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- Definition

Operating Lease, Guaranteed Residual Value of Leased Asset

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No definition available.

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Operating Lease, Unguaranteed Residual Value of Leased Asset

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No definition available.

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Sales-Type and Direct Financing [Abstract]

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No definition available.

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Sales-type, Direct Financing, Operating and Leveraged Leases, Guaranteed Residual Value of Leased Asset

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No definition available.

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- Definition

Sales-type, Direct Financing, Operating and Leveraged Leases, Lease Receivable

+ References

No definition available.

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Sales-type, Direct Financing, Operating and Leveraged Leases, Net Investment

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No definition available.

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Sales-type, Direct Financing, Operating and Leveraged Leases, Net Investment [Abstract]

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Sales-type, Direct Financing, Operating and Leveraged Leases, Unearned Income

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No definition available.

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- Definition

Sales-type, Direct Financing, Operating and Leveraged Leases, Unguaranteed Residual Value of Leased Asset

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No definition available.

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- Definition

Sales-type and Direct Financing Lease, Guaranteed Residual Value of Leased Asset

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No definition available.

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Sales-type and Direct Financing Lease, Unguaranteed Residual Value of Leased Asset

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No definition available.

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Sales-type and Direct Financing Leases [Abstract]

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Sales-type and Direct Financing, Unearned Income

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No definition available.

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- Definition

Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

+ References

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- Definition

Amount of lease payments to be received by lessor for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919396-209981

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- Definition

The total recognized during the period for income on leases meeting the criteria for classification as leveraged leases.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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- Definition

The estimated portion of pretax income and investment tax credit remaining to be allocated to income over the lease term.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

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

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- Definition

Amount of net investment in sales-type and direct financing lease.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of interest income from net investment in sales-type and direct financing leases.

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- Definition

Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

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