Customer Financing (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2020
Customer Financing [Line Items]
Individually evaluated for impairment	$ 391	$ 391	$ 400
Impaired financing receivables	380	380	388
Financing Receivable, Nonaccrual	380	380	388
Financing Receivable, Nonaccrual, Interest Income	8	34
Financing Receivable, Allowance for Credit Loss	(17)	(17)	(8)	$ (5)
Sales-Type and Direct Financing Leases, Lease Income		57	62
Operating Lease, Lease Income		118	139
Operating Lease, Variable Lease Income		9	8
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount	$ 299	$ 299	$ 393
CCC Credit Rating [Member]
Customer Financing [Line Items]
Percentage Of Credit Default Rates Applied To Customers	26.00%	26.00%
B Credit Rating [Member]
Customer Financing [Line Items]
Percentage Of Credit Default Rates Applied To Customers	7.40%	7.40%
BB Credit Rating [Member]
Customer Financing [Line Items]
Percentage Of Credit Default Rates Applied To Customers	3.00%	3.00%
BBB Credit Rating [Member]
Customer Financing [Line Items]
Percentage Of Credit Default Rates Applied To Customers	0.20%	0.20%

Customer Financing [Line Items]

No definition available.

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- Definition

The rate determined from customer credit ratings and weighted average remaining contract term of sales-type/finance leases and notes.

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- Definition

Amount of lease income from variable lease payments, interest income from net investment on Sales-Type and Direct Financing Leases, and profit (loss) recognized at commencement.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

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Amount of financing receivable on nonaccrual status.

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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- Definition

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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Amount of operating lease income from variable lease payments paid and payable to lessor, excluding amount included in measurement of lease receivable.

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- Definition

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

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