Fair Value (Details 4) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Carrying amount and estimated fair value of financial instruments
Fair value	$ 14,291	$ 7,113
Securities available-for-sale	956,239	926,717
Restricted Investments	15,012	15,394
Accrued interest receivable	18,482	18,523
Deposits	(3,604,353)	(3,275,357)
Fair Value, Inputs, Level 1 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	25,428	26,275
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	0	0
Loans Receivable, Fair Value Disclosure	0	0
Accrued interest receivable	0	0
Deposits	0	0
Short-term borrowings	0	0
Accrued interest payable	0	0
Fair Value, Inputs, Level 2 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	363,012	101,151
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	950,968	920,533
Loans Receivable, Fair Value Disclosure	0	0
Accrued interest receivable	5,007	3,583
Deposits	(3,615,014)	(3,278,099)
Short-term borrowings	(95,249)	(80,119)
Accrued interest payable	(1,107)	(1,739)
Fair Value, Inputs, Level 3 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	5,271	6,184
Loans Receivable, Fair Value Disclosure	2,787,631	2,648,692
Accrued interest receivable	13,475	14,940
Deposits	0	0
Short-term borrowings	0	0
Accrued interest payable	0	0
Reported Value Measurement [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	388,440	127,426
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	956,239	926,717
Restricted Investments	15,012	15,394
Loans Receivable, Fair Value Disclosure	2,726,533	2,636,447
Accrued interest receivable	18,482	18,523
Deposits	(3,604,353)	(3,275,357)
Short-term borrowings	(95,249)	(80,119)
Accrued interest payable	(1,107)	(1,739)
Estimate of Fair Value Measurement [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	388,440	127,426
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	956,239	926,717
Loans Receivable, Fair Value Disclosure	2,787,631	2,648,692
Accrued interest receivable	18,482	18,523
Deposits	(3,615,014)	(3,278,099)
Short-term borrowings	(95,249)	(80,119)
Accrued interest payable	$ (1,107)	$ (1,739)

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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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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Fair value portion of federal funds sold and securities borrowed or purchased under agreements to resell.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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