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Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Basis Of Presentation [Line Items] |  |  |  |
Operating lease, right-of-use asset | $ 3,609 |  | $ 3,609 |
Operating lease, liability | 3,633 |  | 3,633 |
Revenue, remaining performance obligation, amount | 0 |  | 0 |
Contract with customer, liability, total | 0 |  | 0 |
Service and Other Charges On Deposit Accounts, Mortgage Fees from Secondary Market Transactions at the Bank, ATM Fee Income and Other Non-Interest Income [Member] |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |
Revenue from Contract with Customer, Including Assessed Tax | 800 | $ 800 | 2,400 | $ 900
Accounting Standards Update 2016-02 [Member] |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |
Operating lease, right-of-use asset | 3,600 |  | 3,600 |
Operating lease, liability | $ 3,600 |  | $ 3,600 |

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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044 + Details
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