Fair Value Disclosures and Reporting and Fair Value Measurements - Carrying Amount and Estimated Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial Assets:
Investment securities available for sale	$ 1,025,032	$ 973,314
Total impaired loans		9,432
Financial liabilities:
Repurchase agreements	107,760	106,937
Carrying Amount [Member]
Financial Assets:
Cash and cash equivalents	253,534	257,528
Investment securities available for sale	1,025,032	973,314
Loans and leases, net held for investment	1,940,933	1,973,207
Collateral dependent loans	18,668	398
Financial liabilities:
Deposits	2,864,943	2,781,572
Repurchase agreements	107,760	106,937
Long-term debt	49,151
Short term borrowings		49,141
Subordinated debentures	35,347	35,302
Fair Value [Member]
Financial Assets:
Cash and cash equivalents	253,534	257,528
Investment securities available for sale	1,025,032	973,314
Loans and leases, net held for investment	1,938,933	1,960,966
Collateral dependent loans	18,668	398
Financial liabilities:
Deposits	2,862,503	2,780,668
Repurchase agreements	107,760	106,937
Long-term debt	46,585
Short term borrowings		49,118
Subordinated debentures	31,404	33,281
Fair Value [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Cash and cash equivalents	253,534	257,528
Investment securities available for sale	0	0
Loans and leases, net held for investment	0	0
Collateral dependent loans	0	0
Financial liabilities:
Deposits	1,104,691	1,084,544
Repurchase agreements	0	0
Long-term debt	0
Short term borrowings		0
Subordinated debentures	0	0
Fair Value [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Cash and cash equivalents	0	0
Investment securities available for sale	984,148	750,077
Loans and leases, net held for investment	0	0
Collateral dependent loans	18,668	221
Financial liabilities:
Deposits	1,757,812	1,696,124
Repurchase agreements	107,760	106,937
Long-term debt	46,585
Short term borrowings		49,118
Subordinated debentures	31,404	33,281
Fair Value [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Cash and cash equivalents	0	0
Investment securities available for sale	40,884	223,237
Loans and leases, net held for investment	1,938,933	1,960,966
Collateral dependent loans	0	177
Financial liabilities:
Deposits	0	0
Repurchase agreements	0	0
Long-term debt	0
Short term borrowings		0
Subordinated debentures	$ 0	$ 0

Loans and leases held for investment.

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- Definition

Other long term debt, fair value disclosure.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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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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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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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

The fair value amount of long-term debt 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.

+ References

No definition available.

+ Details

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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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