Loans to Bank Customers - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Allowance for Loan Losses [Roll Forward]
Balance, beginning of period	$ 570	$ 970	$ 1,166	$ 1,144
Provision for loans	247	658	501	1,914
Loans charged off	(282)	(112)	(1,403)	(1,661)
Recoveries of loans previously charged off	107	42	378	161
Balance, end of period	$ 642	$ 1,558	$ 642	$ 1,558

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

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- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

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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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- Definition

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

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