Loan Servicing - Activity for I/O Strip Receivables (Details) - I/O strip receivables - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Activity for I/O Strip Receivables
Balance, beginning of year	$ 568	$ 968	$ 1,067
Unrealized loss	(65)	(400)	(99)
Balance, end of year	$ 503	$ 568	$ 968

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_ServicingAssetAtAmortizedValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant