Mortgage Servicing Rights - Narrative (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Transfers and Servicing [Abstract]
Mortgage loans serviced for third parties	$ 159,700,000	$ 175,500,000
Valuation allowance for mortgage servicing rights	0	3,000
Fair value of mortgage servicing rights	$ 1,500,000	$ 1,500,000

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

Name:	us-gaap_ServicingAssetAtFairValueAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant