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Loan Servicing (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
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Banking and Thrift [Abstract] |  |  |
Unpaid balance of loans serviced for others | $ 514,294 | $ 533,386 | $ 549,618

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Balance Type: | debit
Period Type: | instant

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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
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