Notes Receivable and Allowance for Credit Losses - Allowance for Credit Loss Rollforward (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 4,556	$ 4,685
Loan reserves	4,556	4,685
Provision for Loan and Lease Losses	4,302	0
Write-offs	(911)	(129)
Ending balance	16,295	4,556
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,348
Loan reserves	$ 8,348	8,348
Ending balance		$ 8,348

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

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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

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