Loans - Schedule of Concentration Risk (Details) - Owners of rental properties - Financing receivable	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Residential
Concentration Risk [Line Items]
Concentration of loans (as a percent)	14.82%	15.00%
Commercial
Concentration Risk [Line Items]
Concentration of loans (as a percent)	12.07%	13.16%

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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