Fair Value of Assets and Liabilities - Schedule Of Estimated Fair Values (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	$ 5,527	$ 5,731
Purchased receivables, net	19,412	22,231
Mortgage servicing rights	8,039	7,305
Derivative liabilities	236	77
Level 1 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	5,527
Mortgage servicing rights	0	0
Derivative liabilities	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	83,962	77,841
Investment securities available for sale	70,540	59,117
Total marketable securities	5,527
Level 1 inputs | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash, due from banks and deposits in other banks	83,962	77,841
Investment securities available for sale	70,540	59,117
Total marketable securities	5,527
Level 2 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Mortgage servicing rights	0	0
Derivative liabilities	236	77
Level 2 inputs | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	227,033	253,633
Investment in Federal Home Loan Bank stock	2,105	2,115
Accrued interest receivable	4,390	4,385
Deposits	1,260,790	1,258,283
Securities sold under repurchase agreements	31,018	27,746
Borrowings	7,338	7,362
Accrued interest payable	58	24
Level 2 inputs | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	227,033	253,633
Investment in Federal Home Loan Bank stock	2,105	2,115
Accrued interest receivable	4,390	4,385
Deposits	1,259,613	1,257,670
Securities sold under repurchase agreements	31,018	27,746
Borrowings	6,993	7,308
Accrued interest payable	58	24
Level 3 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total marketable securities	0
Mortgage servicing rights	8,039	7,305
Derivative liabilities	0	0
Level 3 inputs | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and loans held for sale1	1,008,790	999,445
Purchased receivables, net	19,412	22,231
Mortgage servicing rights	8,039	7,305
Junior subordinated debentures	10,310	10,310
Level 3 inputs | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and loans held for sale1	1,003,372	1,001,346
Purchased receivables, net	19,412	22,231
Mortgage servicing rights	8,039	7,305
Junior subordinated debentures	9,919	9,856
Interest rate swaps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	784	261
Derivative liabilities	133	77
Interest rate swaps | Level 1 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Interest rate swaps | Level 2 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	784	261
Derivative liabilities	133	77
Interest rate swaps | Level 2 inputs | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	784	261
Derivative liabilities	133	77
Interest rate swaps | Level 2 inputs | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	784	261
Derivative liabilities	133	77
Interest rate swaps | Level 3 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Interest rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,323	873
Interest rate lock commitments | Level 1 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Interest rate lock commitments | Level 2 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Interest rate lock commitments | Level 3 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,323	873
Interest rate lock commitments | Level 3 inputs | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,323	873
Interest rate lock commitments | Level 3 inputs | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,323	873
Retail interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	103
Retail interest rate contracts | Level 1 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0
Retail interest rate contracts | Level 2 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	103
Retail interest rate contracts | Level 2 inputs | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	103	0
Retail interest rate contracts | Level 2 inputs | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	103	$ 0
Retail interest rate contracts | Level 3 inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	$ 0