Fair Value of Assets and Liabilities - Schedule of Difference between Aggregate Fair Value and Aggregate Unpaid Principal Balance (Details) - Residential mortgage loans held for sale - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value Option Quantitative Disclosures [Line Items]
Aggregate Fair Value	$ 82,565	$ 39,062
Aggregate Unpaid Principal	78,577	38,293
Aggregate Fair Value Less Aggregate Unpaid Principal	$ 3,988	$ 769