Leases - Net Investment in Direct Finance Leases (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Total minimum lease payments to be received	$ 29	$ 31
Less amounts representing estimated executory costs	(11)	(12)
Minimum lease payments receivable	18	19
Less unearned finance lease income	(9)	(10)
Net investment in direct finance and sales-type leases	9	9
Principal due within one year (included in "Receivables")	(2)	(2)
Net investment in direct finance and sales-type leases - long-term (included in "Other deferred debits")	$ 7	$ 7

Direct financing leases lease amounts representing estimated executory costs.

No definition available.

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- Definition

Direct financing leases lease receivable payments to be received.

+ References

No definition available.

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- Definition

Amount of deferred selling profit from direct financing lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919379-209981

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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 direct financing lease.

+ References

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- References

No definition available.

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- Definition

Amount, before allowance for credit loss, of net investment in sales-type and direct financing leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524

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- Definition

Amount, before allowance for credit loss, of net investment in sales-type and direct financing leases, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=123420820&loc=SL77919306-209978

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- Definition

Amount, before allowance for credit loss, of net investment in sales-type and direct financing leases, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=123420820&loc=SL77919306-209978

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