Loan Servicing (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Servicing Assets at Fair Value [Line Items]
Serviced sold mortgage loans	$ 1,447,000	$ 1,389,000	$ 1,371,000
Serviced sold mortgage loans with recourse	2,300	2,500	3,000
Mortgage loans sold with recourse, reserve	$ 25	$ 60
Mortgage servicing rights, discount rate	12.00%	12.00%
Bank Servicing [Member]
Servicing Assets at Fair Value [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 15,500	$ 14,266	13,162
Bank Servicing [Member] \| Real Estate Loan [Member]
Servicing Assets at Fair Value [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 3,600	$ 3,600	$ 3,500
Minimum
Servicing Assets at Fair Value [Line Items]
Mortgage servicing rights, constant prepayment speeds	6.60%	4.80%
Maximum
Servicing Assets at Fair Value [Line Items]
Mortgage servicing rights, constant prepayment speeds	18.42%	17.82%
Mortgages [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Asset at Amortized Cost, Fair Value	$ 10,100	$ 11,000

Mortgage Loans Sold with Recourse, Reserve

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- Definition

Principal Amount Outstanding On Sold Loans Servicing Retained

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- Definition

Principal Amount Outstanding On Sold Loans Servicing Retained With Recourse

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- Definition

Estimated rate of prepayment of principal on financial assets for initial fair value measurement.

+ References

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Amount, including 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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