Notes Receivable (Schedule Of Allowance For Loan Losses) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Notes, Loans, And Financing Receivable, Net Rollforward [Roll Forward]
Allowance for loan losses, at beginning of period	$ 24	$ 20
Charge-offs	(35)	(24)
Recoveries	6	3
Provision for loan losses	38	25
Allowance for loan losses, at end of period	$ 33	$ 24

Notes, Loans, And Financing Receivable, Net Rollforward [Roll Forward]

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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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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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