Fair Value - Aggregate Fair Value and Contractual Balance of Loans for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Value of loans held for sale	$ 73,046	$ 20,029
Excess	1,944	584
Contractual Balance
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Value of loans held for sale	$ 71,102	$ 19,445