Fair Value - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets
Securities available-for-sale	$ 390,107	$ 306,589
Securities held-to-maturity	377,845	318,748
I/O strips receivables	989	1,067
Liabilities
Subordinated Debt.	39,137
Significant Other Observable Inputs (Level 2)
Assets
I/O strips receivables	989	1,067
Carrying amount
Assets
Cash and cash equivalents	346,120	266,103
Securities available-for-sale	390,107	306,589
Securities held-to-maturity	379,550	324,010
Loans (including loans held-for-sale), net	1,550,804	1,489,223
FHLB and FRB stock and other investments	17,905	15,196
Accrued interest receivable	7,818	6,859
I/O strips receivables	989	1,067
Liabilities
Time deposits	204,291	224,717
Other deposits	2,276,313	2,037,423
Subordinated Debt.	39,137
Accrued interest payable	934	168
Carried at fair value
Assets
Cash and cash equivalents	346,120	266,103
Securities available-for-sale	390,107	306,589
Securities held-to-maturity	377,845	318,748
Loans (including loans held-for-sale), net	1,501,612	1,449,781
Accrued interest receivable	7,818	6,859
I/O strips receivables	989	1,067
Liabilities
Time deposits	204,555	225,047
Other deposits	2,276,313	2,037,423
Subordinated Debt.	39,937
Accrued interest payable	934	168
Carried at fair value \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Cash and cash equivalents	346,120	266,103
Carried at fair value \| Significant Other Observable Inputs (Level 2)
Assets
Securities available-for-sale	390,107	306,589
Securities held-to-maturity	377,845	318,748
Loans (including loans held-for-sale), net	4,602	5,705
Accrued interest receivable	2,522	1,961
I/O strips receivables	989	1,067
Liabilities
Time deposits	204,555	225,047
Other deposits	2,276,313	2,037,423
Subordinated Debt.	39,937
Accrued interest payable	934	168
Carried at fair value \| Significant Unobservable Inputs (Level 3)
Assets
Loans (including loans held-for-sale), net	1,497,010	1,444,076
Accrued interest receivable	$ 5,296	$ 4,898

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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-SubTopic 10
-Section S99
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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 investments in debt securities classified as 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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The aggregate value of all restricted investments.

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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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