Fair Value of Assets and Liabilities - Schedule Of Estimated Fair Values (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	$ 264,124	$ 307,019
Total marketable equity securities	6,006	5,731
Purchased receivables, net	20,323	22,231
Mortgage servicing rights	8,733	7,305
Derivative liabilities	285	77
Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	956	261
Derivative liabilities	151	77
Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,417	873
Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	134
Level 1 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	60,175	53,386
Total marketable equity securities	6,006
Mortgage servicing rights	0	0
Derivative liabilities	0	0
Level 1 inputs \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Level 1 inputs \| Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Level 1 inputs \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0
Level 1 inputs \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, due from banks and deposits in other banks	36,130	77,841
Investment securities available for sale, at fair value	60,175
Investment securities available for sale		59,117
Total marketable equity securities	6,006
Level 1 inputs \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, due from banks and deposits in other banks	36,130	77,841
Investment securities available for sale, at fair value	60,175
Investment securities available for sale		59,117
Total marketable equity securities	6,006
Level 2 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	203,949	253,633
Total marketable equity securities	0
Mortgage servicing rights	0	0
Derivative liabilities	285	77
Level 2 inputs \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	956	261
Derivative liabilities	151	77
Level 2 inputs \| Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Level 2 inputs \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	134
Level 2 inputs \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	203,949
Investment securities available for sale		253,633
Investment in Federal Home Loan Bank stock	2,104	2,115
Accrued interest receivable	4,489	4,385
Deposits	1,205,521	1,258,283
Securities sold under repurchase agreements	27,695	27,746
Borrowings	7,312	7,362
Accrued interest payable	91	24
Level 2 inputs \| Carrying Amount \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	956	261
Derivative liabilities	151	77
Level 2 inputs \| Carrying Amount \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	134	0
Level 2 inputs \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	203,949
Investment securities available for sale		253,633
Investment in Federal Home Loan Bank stock	2,104	2,115
Accrued interest receivable	4,489	4,385
Deposits	1,204,467	1,257,670
Securities sold under repurchase agreements	27,695	27,746
Borrowings	7,023	7,308
Accrued interest payable	91	24
Level 2 inputs \| Fair Value \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	956	261
Derivative liabilities	151	77
Level 2 inputs \| Fair Value \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	134	0
Level 3 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	0	0
Total marketable equity securities	0
Mortgage servicing rights	8,733	7,305
Derivative liabilities	0	0
Level 3 inputs \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Level 3 inputs \| Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,417	873
Level 3 inputs \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0
Level 3 inputs \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and loans held for sale1	1,022,008	999,445
Purchased receivables, net	20,323	22,231
Mortgage servicing rights	8,733	7,305
Junior subordinated debentures	10,310	10,310
Level 3 inputs \| Carrying Amount \| Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,417	873
Level 3 inputs \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and loans held for sale1	995,564	1,001,346
Purchased receivables, net	20,323	22,231
Mortgage servicing rights	8,733	7,305
Junior subordinated debentures	10,202	9,856
Level 3 inputs \| Fair Value \| Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	$ 1,417	$ 873

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Loans And Loans Held For Sale Fair Value Disclosure

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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 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, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value of obligations measured on a recurring basis.

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

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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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