Loans - Schedule of Concentration Risk (Details) - Owners of rental properties - Financing receivable	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Residential
Concentration Risk [Line Items]
Concentration of loans (as a percent)	16.29%	15.41%
Commercial
Concentration Risk [Line Items]
Concentration of loans (as a percent)	12.98%	12.19%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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