Revenue From Contracts With Customers - Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Revenue From Contracts With Customers [Abstract]
Receivables, which are included in "Other assets"	$ 976	$ 1,046
Contract assets, which are included in "Other assets"	0	0
Contract liabilities, which are included in "Accrued interest payable and other liabilities"	$ 327	$ 359

Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130551-203045

Name:	us-gaap_ContractWithCustomerAssetReclassifiedToReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration