Fair Value Disclosures and Reporting, the Fair Value Option and Fair Value Measurements - Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financial Assets:
Securities available-for-sale	$ 620,154	$ 600,799
Financial liabilities:
Repurchase agreements	29,361	25,711
Carrying Amount [Member]
Financial Assets:
Cash and cash equivalents	106,992	80,077
Securities available-for-sale	620,154	600,799
Loans and leases, net held for investment	1,787,101	1,753,846
Collateral dependent impaired loans	2,212	1,692
Financial liabilities:
Deposits	2,179,391	2,168,374
Repurchase agreements	29,361	25,711
Short term borrowings	74,100	20,000
Subordinated debentures	34,990	34,945
Fair Value [Member]
Financial Assets:
Cash and cash equivalents	106,992	80,076
Securities available-for-sale	620,154	600,799
Loans and leases, net held for investment	1,834,373	1,761,461
Collateral dependent impaired loans	2,212	1,692
Financial liabilities:
Deposits	2,179,182	2,168,447
Repurchase agreements	29,361	25,711
Short term borrowings	74,100	20,000
Subordinated debentures	29,911	30,564
Fair Value [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Cash and cash equivalents	106,992	80,076
Securities available-for-sale	0	0
Loans and leases, net held for investment	0	0
Collateral dependent impaired loans	0	0
Financial liabilities:
Deposits	704,700	690,950
Repurchase agreements	0	0
Short term borrowings	0	0
Subordinated debentures	0	0
Fair Value [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Cash and cash equivalents	0	0
Securities available-for-sale	620,154	600,799
Loans and leases, net held for investment	0	0
Collateral dependent impaired loans	2,212	1,692
Financial liabilities:
Deposits	1,474,482	1,477,497
Repurchase agreements	29,361	25,711
Short term borrowings	74,100	20,000
Subordinated debentures	29,911	30,564
Fair Value [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Cash and cash equivalents	0	0
Securities available-for-sale	0	0
Loans and leases, net held for investment	1,834,373	1,761,461
Collateral dependent impaired loans	0	0
Financial liabilities:
Deposits	0	0
Repurchase agreements	0	0
Short term borrowings	0	0
Subordinated debentures	$ 0	$ 0

Loans and leases held for investment.

No definition available.

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- Definition

Other long term debt, fair value disclosure.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&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 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&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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- References

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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

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

No definition available.

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