Fair Value Measurements - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financial assets:
Available-for-sale securities, at fair value	$ 582,183	$ 649,387
Interest receivable	7,241	6,763
Derivatives assets	19,745	6,023
Financial liabilities:
Derivatives liabilities	586	369
Carrying Amount
Financial assets:
Cash and cash equivalents	136,327	97,723
Available-for-sale securities, at fair value	582,183	649,387
Federal Home Loan Bank Stock	7,743	6,528
Loans, net	1,827,037	1,677,403
Loans held for sale	507,442	273,196
Interest receivable	7,241	6,763
Mortgage servicing rights, net	32,070	29,711
Derivatives assets	19,745	6,023
Financial liabilities:
Deposits, Without stated maturities	2,280,531	2,112,915
Deposits, With stated maturities	391,031	325,559
Securities sold under agreement to repurchase	21,561	105,133
Short term borrowings	150,000	18,000
Interest payable	620	550
Long-term debt	44,892	56,616
Derivatives liabilities	586	369
Fair Value
Financial assets:
Cash and cash equivalents	136,327	97,723
Available-for-sale securities, at fair value	582,183	649,387
Federal Home Loan Bank Stock	7,743	6,528
Loans, net	1,823,335	1,675,457
Loans held for sale	507,442	273,196
Interest receivable	7,241	6,763
Mortgage servicing rights, net	32,070	29,711
Derivatives assets	19,745	6,023
Financial liabilities:
Deposits, Without stated maturities	2,280,531	2,112,915
Deposits, With stated maturities	390,484	323,624
Securities sold under agreement to repurchase	21,561	105,133
Short term borrowings	150,000	18,000
Interest payable	620	550
Long-term debt	43,994	55,484
Derivatives liabilities	586	369
Fair Value \| Fair Value Level 1
Financial assets:
Cash and cash equivalents	136,327	97,723
Financial liabilities:
Deposits, Without stated maturities	2,280,531	2,112,915
Securities sold under agreement to repurchase	21,561	105,133
Short term borrowings	150,000	18,000
Interest payable	237	244
Fair Value \| Fair Value Level 2
Financial assets:
Available-for-sale securities, at fair value	577,634	644,531
Loans, net	1,822,054	1,638,506
Loans held for sale	507,442	273,196
Interest receivable	7,241	6,763
Derivatives assets	19,745	6,023
Financial liabilities:
Deposits, With stated maturities	390,484	323,624
Interest payable	383	306
Long-term debt	43,994	55,484
Derivatives liabilities	586	369
Fair Value \| Fair Value Level 3
Financial assets:
Available-for-sale securities, at fair value	4,549	4,856
Federal Home Loan Bank Stock	7,743	6,528
Loans, net	1,281	36,951
Mortgage servicing rights, net	$ 32,070	$ 29,711

Deposits with stated maturities fair value disclosure.

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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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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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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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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.

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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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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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