Notes Receivable - Schedule of Allowance For Loan Losses (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Jan. 01, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 33
Effects of new accounting standard	99
Provisions for loan losses	13
Charge-offs	(11)
Recoveries	2
Balance at end of period	$ 99
Cumulative Effect, Period Of Adoption, Adjustment, Pre-tax
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Effects of new accounting standard		$ 62

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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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Amount of credit loss expense (reversal of expense) for financing receivable.

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