Mortgage Servicing Rights - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
(Positive) negative valuation adjustment to MSR	$ (13,561)	$ 9,571	$ 11,726
Bank Servicing
Disaggregation of Revenue [Line Items]
Revenue	$ 4,071	$ 2,623

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details