Fair Value of Assets and Liabilities - Schedule Of Estimated Fair Values (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	$ 264,193	$ 307,019
Total marketable equity securities	6,035	5,731
Purchased receivables, net	12,706	22,231
Mortgage servicing rights	9,695	7,305
Derivative liabilities	122	77
Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,161	261
Derivative liabilities	122	77
Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,117	873
Level 1 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	75,165	53,386
Total marketable equity securities	6,035
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 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, due from banks and deposits in other banks	70,179	77,841
Investment securities available for sale, at fair value	75,165
Investment securities available for sale		59,117
Total marketable equity securities	6,035
Level 1 inputs \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, due from banks and deposits in other banks	70,179	77,841
Investment securities available for sale, at fair value	75,165
Investment securities available for sale		59,117
Total marketable equity securities	6,035
Level 2 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	189,028	253,633
Total marketable equity securities	0
Mortgage servicing rights	0	0
Derivative liabilities	122	77
Level 2 inputs \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,161	261
Derivative liabilities	122	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 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	189,028
Investment securities available for sale		253,633
Investment in Federal Home Loan Bank stock	2,103	2,115
Accrued interest receivable	4,787	4,385
Deposits	1,233,268	1,258,283
Securities sold under repurchase agreements	32,429	27,746
Borrowings	7,282	7,362
Accrued interest payable	125	24
Level 2 inputs \| Carrying Amount \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,161	261
Derivative liabilities	122	77
Level 2 inputs \| Carrying Amount \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Level 2 inputs \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale, at fair value	189,028
Investment securities available for sale		253,633
Investment in Federal Home Loan Bank stock	2,103	2,115
Accrued interest receivable	4,787	4,385
Deposits	1,231,850	1,257,670
Securities sold under repurchase agreements	32,429	27,746
Borrowings	6,901	7,308
Accrued interest payable	125	24
Level 2 inputs \| Fair Value \| Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,161	261
Derivative liabilities	122	77
Level 2 inputs \| Fair Value \| Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	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	9,695	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	1,117	873
Level 3 inputs \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and loans held for sale1	1,038,643	999,445
Purchased receivables, net	12,706	22,231
Mortgage servicing rights	9,695	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	1,117	873
Level 3 inputs \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and loans held for sale1	1,006,152	1,001,346
Purchased receivables, net	12,706	22,231
Mortgage servicing rights	9,695	7,305
Junior subordinated debentures	10,001	9,856
Level 3 inputs \| Fair Value \| Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	$ 1,117	$ 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 securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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