Leasing (Sales-type and Direct Financing Leases, Lease Receivable, Maturity) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Leases [Abstract]
Direct financing lease, net investment in lease	$ 525		$ 525		$ 481
Direct financing lease, present value of lease payments recorded as lease receivable	519		519		468
Direct financing lease, unguaranteed residual asset	6		6		$ 13
Direct financing lease, interest income	10	$ 8	28	$ 22
2023	53		53
2024	172		172
2025	149		149
2026	119		119
2027	59		59
2028 and thereafter	33		33
Total undiscounted cash flows	585		585
Difference between undiscounted cash flows and discounted cash flows	(66)		(66)
Present value of lease payments recorded as lease receivable	$ 519		$ 519

Sales-Type And Direct Financing Leases, Lease Receivable, To Be Received, After Year Four

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- Definition

Amount of interest income from net investment in direct financing lease.

+ References

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-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
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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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Amount excluding accrued interest, before allowance for credit loss, of net investment in direct financing lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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-Publisher FASB
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Present value expected to be derived from underlying asset, following end of lease term, not guaranteed by lessee or other third party unrelated to lessor.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 30
-Name Accounting Standards Codification
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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted lease receivable in excess of discounted receivable for sales-type and direct financing leases.

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