Fair Value Measurements Not Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
FINANCIAL ASSETS:
Investment securities held-to-maturity	$ 53,929	$ 68,595
Book Value
FINANCIAL ASSETS:
Cash and cash equivalents	65,756	127,259
Investment securities held-to-maturity	54,482	70,438
Loans held for sale	3,640	2,812
Loans, net	7,005,193	6,817,846
Other financial assets	94,475	78,730
FINANCIAL LIABILITIES:
Deposits	6,437,963	6,781,170
Securities sold under agreements to repurchase	62,372	36,928
Federal funds purchased	135,000	250,000
Federal Home Loan Bank borrowings	920,068	420,144
Junior subordinated debentures	106,363	106,363
Other financial liabilities	4,386	2,001
Fair Value
FINANCIAL ASSETS:
Cash and cash equivalents	65,756	127,259
Investment securities held-to-maturity	53,929	68,595
Loans held for sale	3,713	2,837
Loans, net	6,988,207	6,734,216
Other financial assets	94,475	78,730
FINANCIAL LIABILITIES:
Deposits	6,437,827	6,777,928
Securities sold under agreements to repurchase	62,372	36,928
Federal funds purchased	135,000	250,000
Federal Home Loan Bank borrowings	920,615	417,092
Junior subordinated debentures	96,363	96,363
Other financial liabilities	4,386	2,001
Fair Value \| Quoted prices in active markets for identical assets (Level 1)
FINANCIAL ASSETS:
Cash and cash equivalents	65,756	127,259
Investment securities held-to-maturity	0	0
Loans held for sale	0	0
Loans, net	0	0
Other financial assets	0	0
FINANCIAL LIABILITIES:
Deposits	0	0
Securities sold under agreements to repurchase	0	0
Federal funds purchased	0	0
Federal Home Loan Bank borrowings	0	0
Junior subordinated debentures	0	0
Other financial liabilities	0	0
Fair Value \| Significant other observable inputs (Level 2)
FINANCIAL ASSETS:
Cash and cash equivalents	0	0
Investment securities held-to-maturity	53,929	68,595
Loans held for sale	3,713	2,837
Loans, net	0	0
Other financial assets	94,475	78,730
FINANCIAL LIABILITIES:
Deposits	6,437,827	6,777,928
Securities sold under agreements to repurchase	62,372	36,928
Federal funds purchased	135,000	250,000
Federal Home Loan Bank borrowings	920,615	417,092
Junior subordinated debentures	0	0
Other financial liabilities	4,386	2,001
Fair Value \| Significant unobservable inputs (Level 3)
FINANCIAL ASSETS:
Cash and cash equivalents	0	0
Investment securities held-to-maturity	0	0
Loans held for sale	0	0
Loans, net	6,988,207	6,734,216
Other financial assets	0	0
FINANCIAL LIABILITIES:
Deposits	0	0
Securities sold under agreements to repurchase	0	0
Federal funds purchased	0	0
Federal Home Loan Bank borrowings	0	0
Junior subordinated debentures	96,363	96,363
Other financial liabilities	$ 0	$ 0

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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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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.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value portion of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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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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Fair value portion of other assets.

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Fair value portion of other liabilities.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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