Short-Term Borrowings (Details) - USD ($)		3 Months Ended
Apr. 30, 2015	Mar. 31, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Weighted Average Rate		0.90%	1.17%
Short-term borrowings		$ 129,489,000	$ 139,349,000
Pledged securities		$ 334,700,000	$ 264,800,000
Securities sold under agreements to repurchase
Short-term Debt [Line Items]
Weighted Average Rate		0.90%	1.06%
Short-term borrowings		$ 129,489,000	$ 117,249,000
Federal Home Loan Bank advances
Short-term Debt [Line Items]
Weighted Average Rate		0.00%	1.73%
Short-term borrowings		$ 0	$ 22,100,000
Federal funds purchased
Short-term Debt [Line Items]
Short-term borrowings		0	0
Unsercured line of credit, maximum borrowing capacity		170,000,000.0
Federal Reserve Bank advances
Short-term Debt [Line Items]
Short-term borrowings		0	0
Financing capacity		61,500,000	12,700,000
Pledged securities		68,300,000	13,000,000.0
Line of credit
Short-term Debt [Line Items]
Short-term borrowings		0	$ 0
Unsercured line of credit, maximum borrowing capacity	$ 5,000,000.0	$ 10,000,000.0
Line of credit \| LIBOR
Short-term Debt [Line Items]
Debt instrument, basis spread on variable rate	2.00%	1.75%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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