Leasing Activity, Maturities of Lease Receivables (Details) $ in Millions	Dec. 31, 2020 USD ($)
Sales-type and Direct Financing Leases, Lease Receivable, Fiscal Year Maturity [Abstract]
2021, direct financing and sales-type leases, lessor	$ 5,060
2022, direct financing and sales-type leases, lessor	3,650
2023, direct financing and sales-type leases, lessor	2,259
2024, direct financing and sales-type leases, lessor	1,274
2025, direct financing and sales-type leases, lessor	630
Thereafter, direct financing and sales-type leases, lessor	1,337
Total lease receivable, direct financing and sales-type leases, lessor	14,210
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
2021, operating leases. lessor	655
2022, operating leases, lessor	461
2023, operating leases, lessor	330
2024, operating leases, lessor	227
2025, operating leases, lessor	153
Thereafter, operating leases, lessor	265
Total lease receivables, operating leases, lessor	$ 2,091

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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=121576215&loc=SL77919396-209981

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Amount of lease payment to be received by lessor for operating lease in fifth 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 lease payment to be received by lessor for operating lease 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 lease payment to be received by lessor for operating lease 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 lease payment to be received by lessor for operating lease after fifth 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 lease payment to be received by lessor for operating lease 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 lease payment to be received by lessor for operating lease 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 cash flows to be received by lessor for sales-type and direct financing leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919391-209981

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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 after fifth 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 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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