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Summary of Significant Accounting Policies - Revenue Recognition (Details) - Credit Card	9 Months Ended
	Sep. 30, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Commitment and Origination Fees and Discounts or Premiums, Amortization Period	12 months
Amortization term of annual membership fees	12 months

X

- Definition

Amortization term of credit card annual membership fees

+ References

No definition available.

+ Details

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X

- Definition

Loan Commitment and Origination Fees and Discounts or Premiums, Amortization Period

+ References

No definition available.

+ Details

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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X

- Details

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