Fair Value - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Securities available-for-sale	$ 404,825	$ 459,043
Securities held-to-maturity	368,107	366,175
Federal Home Loan Bank, Federal Reserve Bank stock and other investments, at cost	29,842	25,216
I/O strips receivables	503	568
Liabilities
Subordinated Debt.	39,554	39,369
Significant Other Observable Inputs (Level 2)
Assets
I/O strips receivables	503	568
Carrying amount
Assets
Cash and cash equivalents	457,370	164,568
Securities available-for-sale	404,825	459,043
Securities held-to-maturity	366,560	377,198
Loans (including loans held-for-sale), net	2,511,611	1,861,206
Federal Home Loan Bank, Federal Reserve Bank stock and other investments, at cost	29,842	25,216
Accrued interest receivable	10,915	9,577
I/O strips receivables	503	568
Liabilities
Time deposits	168,034	147,560
Other deposits	3,246,734	2,489,972
Subordinated Debt.	39,554	39,369
Accrued interest payable	707	497
Carried at fair value
Assets
Cash and cash equivalents	457,370	164,568
Securities available-for-sale	404,825	459,043
Securities held-to-maturity	368,107	366,175
Loans (including loans held-for-sale), net	2,513,329	1,829,303
Accrued interest receivable	10,915	9,577
I/O strips receivables	503	568
Liabilities
Time deposits	158,704	147,916
Other deposits	3,246,734	2,489,972
Subordinated Debt.	40,404	38,969
Accrued interest payable	707	497
Carried at fair value \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Cash and cash equivalents	457,370	164,568
Securities available-for-sale	120,464	148,753
Accrued interest receivable	446	597
Carried at fair value \| Significant Other Observable Inputs (Level 2)
Assets
Securities available-for-sale	284,361	310,290
Securities held-to-maturity	368,107	366,175
Loans (including loans held-for-sale), net	1,052	2,649
Accrued interest receivable	2,218	2,274
I/O strips receivables	503	568
Liabilities
Time deposits	158,704	147,916
Other deposits	3,246,734	2,489,972
Subordinated Debt.	40,404	38,969
Accrued interest payable	707	497
Carried at fair value \| Significant Unobservable Inputs (Level 3)
Assets
Loans (including loans held-for-sale), net	2,512,277	1,826,654
Accrued interest receivable	$ 8,251	$ 6,706

Fair value as of the balance sheet date of accrued interest receivable.

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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 fair value of deposits other than time deposits as of the balance sheet date.

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Fair value of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required.

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Fair value portion of accrued expenses.

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

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

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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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Amount of investments classified as other.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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