Fair Value (Details 4) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Carrying amount and estimated fair value of financial instruments
Securities available-for-sale	$ 1,097,093	$ 1,020,744
Restricted Investments	14,825	14,812
Accrued interest receivable	15,465	16,957
Deposits	(3,905,348)	(3,755,945)
Fair Value, Inputs, Level 1 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	28,588	25,645
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	638,258	631,825
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	585
Securities available-for-sale	1,091,870	1,015,713
Loans Receivable, Fair Value Disclosure	0	0
Accrued interest receivable	5,188	3,521
Deposits	(3,914,133)	(3,763,358)
Short-term borrowings	(98,775)	(116,061)
Accrued interest payable	(801)	(1,033)
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	5,223	5,031
Loans Receivable, Fair Value Disclosure	2,541,807	2,560,683
Accrued interest receivable	10,277	13,436
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	666,846	657,470
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	585
Securities available-for-sale	1,097,093	1,020,744
Restricted Investments	14,825	14,812
Loans Receivable, Fair Value Disclosure	2,600,161	2,563,242
Accrued interest receivable	15,465	16,957
Deposits	(3,905,348)	(3,755,945)
Short-term borrowings	(98,775)	(116,061)
Accrued interest payable	(801)	(1,033)
Estimate of Fair Value Measurement [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	666,846	657,470
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	585
Securities available-for-sale	1,097,093	1,020,744
Loans Receivable, Fair Value Disclosure	2,541,807	2,560,683
Accrued interest receivable	15,465	16,957
Deposits	(3,914,133)	(3,763,358)
Short-term borrowings	(98,775)	(116,061)
Accrued interest payable	$ (801)	$ (1,033)

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

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- Definition

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.

+ References

No definition available.

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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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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

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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- Definition

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.

+ References

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