Loans and Asset Quality - Schedule of Loans Impaired (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Unpaid Principal Balance
With no related allowance recorded:	$ 4,254	$ 4,407
With allowance recorded:	9,982	10,150
Total impaired loans	14,236	14,557
Recorded Investment
With no related allowance recorded:	3,838	3,997
With allowance recorded:	8,577	8,745
Total impaired loans	12,415	12,742
Related Allowance	3,137	3,288
Average Recorded Investment
With no related allowance recorded:	3,917	7,611
With allowance recorded:	8,662	9,326
Total impaired loans	12,579	16,937
Commercial and industrial
Unpaid Principal Balance
With no related allowance recorded:	1,759	1,805
With allowance recorded:	8,526	8,544
Recorded Investment
With no related allowance recorded:	1,426	1,474
With allowance recorded:	7,306	7,323
Related Allowance	2,785	2,916
Average Recorded Investment
With no related allowance recorded:	1,450	3,685
With allowance recorded:	7,314	7,746
Tax-exempt
Unpaid Principal Balance
With no related allowance recorded:	0	0
With allowance recorded:	0	0
Recorded Investment
With no related allowance recorded:	0	0
With allowance recorded:	0	0
Related Allowance	0	0
Average Recorded Investment
With no related allowance recorded:	0	0
With allowance recorded:	0	0
Consumer
Unpaid Principal Balance
With no related allowance recorded:	2	2
With allowance recorded:	66	76
Recorded Investment
With no related allowance recorded:	2	2
With allowance recorded:	62	73
Related Allowance	62	71
Average Recorded Investment
With no related allowance recorded:	2	9
With allowance recorded:	68	76
Commercial real estate \| Real estate
Unpaid Principal Balance
With no related allowance recorded:	1,359	1,560
With allowance recorded:	1,269	1,263
Recorded Investment
With no related allowance recorded:	1,334	1,537
With allowance recorded:	1,093	1,102
Related Allowance	250	260
Average Recorded Investment
With no related allowance recorded:	1,435	2,647
With allowance recorded:	1,098	1,076
One-to-four family residential \| Real estate
Unpaid Principal Balance
With no related allowance recorded:	1,134	1,040
With allowance recorded:	121	216
Recorded Investment
With no related allowance recorded:	1,076	984
With allowance recorded:	116	209
Related Allowance	40	31
Average Recorded Investment
With no related allowance recorded:	1,030	1,194
With allowance recorded:	163	339
Construction and development \| Real estate
Unpaid Principal Balance
With no related allowance recorded:	0	0
With allowance recorded:	0	51
Recorded Investment
With no related allowance recorded:	0	0
With allowance recorded:	0	38
Related Allowance	0	10
Average Recorded Investment
With no related allowance recorded:	0	76
With allowance recorded:	$ 19	$ 89

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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-Name Accounting Standards Codification
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