Debt - Repayments of Principal and Interest (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total Debt	$ 92,561	$ 92,425
Interest payments in 2022	1,864
Interest payments in 2023	1,350
Interest payments in 2024	908
Interest payments in 2025	554
Interest payments in 2026	361
Interest payments thereafter	575
Interest payments	5,612
Total repayments in 2022	35,197
Total repayments in 2023	21,627
Total repayments in 2024	14,225
Total repayments in 2025	9,212
Total repayments in 2026	6,442
Total repayments thereafter	11,446
Total repayments of principal and interest	98,149
Secured Debt
Debt Instrument [Line Items]
Repayments of principal in 2022	19,996
Repayments of principal in 2023	11,732
Repayments of principal in 2024	5,033
Repayments of principal in 2025	1,895
Repayments of principal in 2026	76
Repayments of principal thereafter	672
Total Debt	39,404
Unsecured Debt
Debt Instrument [Line Items]
Repayments of principal in 2022	13,337
Repayments of principal in 2023	8,545
Repayments of principal in 2024	8,284
Repayments of principal in 2025	6,763
Repayments of principal in 2026	6,005
Repayments of principal thereafter	10,199
Total Debt	$ 53,133

Amount of interest payments scheduled after the fifth fiscal year following the latest fiscal year.

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Amount of interest payments scheduled in the fifth fiscal year following the latest fiscal year.

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Amount of interest payments scheduled in the third fiscal year following the latest fiscal year.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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