Loans and Allowance for Loan Losses - Impaired Loan Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Related Allowance	$ 546	$ 631
Total impaired loans, Recorded Investment	7,451	4,173
Total impaired loans, Unpaid Principal Balance	7,674	4,570
Total impaired loans, Average Recorded Investment	5,118	5,172
Total impaired loans, Interest Income Recognized	204	113
All Other Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans without a valuation allowance, Recorded Investment	4,759	1,356
Impaired loans without a valuation allowance, Unpaid Principal Balance	4,760	1,361
Impaired loans with a valuation allowance, Recorded Investment	574	1,154
Impaired loans with a valuation allowance, Unpaid Principal Balance	574	1,154
Impaired loans with a valuation allowance, Related Allowance	237	475
Impaired loans without a valuation allowance, Average Recorded Investment	2,005	1,774
Impaired loans without a valuation allowance, Interest Income Recognized	45	52
Impaired loans with a valuation allowance, Average Recorded Investment	1,058	870
Impaired loans with a valuation allowance, Interest Income Recognized	34	34
All Other Loans [Member] \| Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans without a valuation allowance, Recorded Investment	3,871	256
Impaired loans without a valuation allowance, Unpaid Principal Balance	3,872	261
Impaired loans with a valuation allowance, Recorded Investment	0	0
Impaired loans with a valuation allowance, Unpaid Principal Balance	0	0
Impaired loans with a valuation allowance, Related Allowance	0	0
Impaired loans without a valuation allowance, Average Recorded Investment	1,073	399
Impaired loans without a valuation allowance, Interest Income Recognized	12	30
Impaired loans with a valuation allowance, Average Recorded Investment	158	9
Impaired loans with a valuation allowance, Interest Income Recognized	2	1
All Other Loans [Member] \| Consumer Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans without a valuation allowance, Recorded Investment	888	553
Impaired loans without a valuation allowance, Unpaid Principal Balance	888	553
Impaired loans with a valuation allowance, Recorded Investment	428	994
Impaired loans with a valuation allowance, Unpaid Principal Balance	428	994
Impaired loans with a valuation allowance, Related Allowance	116	343
Impaired loans without a valuation allowance, Average Recorded Investment	701	725
Impaired loans without a valuation allowance, Interest Income Recognized	33	15
Impaired loans with a valuation allowance, Average Recorded Investment	656	397
Impaired loans with a valuation allowance, Interest Income Recognized	24	17
All Other Loans [Member] \| Construction and Land Development [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans without a valuation allowance, Recorded Investment	0	547
Impaired loans without a valuation allowance, Unpaid Principal Balance	0	547
Impaired loans with a valuation allowance, Recorded Investment	0	0
Impaired loans with a valuation allowance, Unpaid Principal Balance	0	0
Impaired loans with a valuation allowance, Related Allowance	0	0
Impaired loans without a valuation allowance, Average Recorded Investment	231	619
Impaired loans without a valuation allowance, Interest Income Recognized		5
Impaired loans with a valuation allowance, Average Recorded Investment		11
All Other Loans [Member] \| Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans without a valuation allowance, Recorded Investment	0	0
Impaired loans without a valuation allowance, Unpaid Principal Balance	0	0
Impaired loans with a valuation allowance, Recorded Investment	146	160
Impaired loans with a valuation allowance, Unpaid Principal Balance	146	160
Impaired loans with a valuation allowance, Related Allowance	121	132
Impaired loans without a valuation allowance, Average Recorded Investment		20
Impaired loans without a valuation allowance, Interest Income Recognized		1
Impaired loans with a valuation allowance, Average Recorded Investment	244	430
Impaired loans with a valuation allowance, Interest Income Recognized	8	16
All Other Loans [Member] \| Consumer and Other [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans without a valuation allowance, Recorded Investment	0	0
Impaired loans without a valuation allowance, Unpaid Principal Balance	0	0
Impaired loans with a valuation allowance, Recorded Investment	0	0
Impaired loans with a valuation allowance, Unpaid Principal Balance	0	0
Impaired loans with a valuation allowance, Related Allowance	0	0
Impaired loans without a valuation allowance, Average Recorded Investment		11
Impaired loans without a valuation allowance, Interest Income Recognized		1
Impaired loans with a valuation allowance, Average Recorded Investment		23
Purchased Credit Impaired Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Recorded Investment	2,118	1,663
Impaired loans with a valuation allowance, Unpaid Principal Balance	2,340	2,055
Impaired loans with a valuation allowance, Related Allowance	309	156
Impaired loans with a valuation allowance, Average Recorded Investment	2,055	2,528
Impaired loans with a valuation allowance, Interest Income Recognized	125	27
Purchased Credit Impaired Loans [Member] \| Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Recorded Investment	0	17
Impaired loans with a valuation allowance, Unpaid Principal Balance	0	99
Impaired loans with a valuation allowance, Related Allowance	0	17
Impaired loans with a valuation allowance, Average Recorded Investment	200	1,518
Impaired loans with a valuation allowance, Interest Income Recognized	1
Impaired loans with a valuation allowance, Interest Income (Expense) Recognized		(25)
Purchased Credit Impaired Loans [Member] \| Consumer Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Recorded Investment	1,827	1,205
Impaired loans with a valuation allowance, Unpaid Principal Balance	2,086	1,371
Impaired loans with a valuation allowance, Related Allowance	88	74
Impaired loans with a valuation allowance, Average Recorded Investment	1,461	922
Impaired loans with a valuation allowance, Interest Income Recognized	117	42
Purchased Credit Impaired Loans [Member] \| Construction and Land Development [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Recorded Investment	0	0
Impaired loans with a valuation allowance, Unpaid Principal Balance	0	0
Impaired loans with a valuation allowance, Related Allowance	0	0
Impaired loans with a valuation allowance, Average Recorded Investment	46
Purchased Credit Impaired Loans [Member] \| Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Recorded Investment	270	396
Impaired loans with a valuation allowance, Unpaid Principal Balance	234	534
Impaired loans with a valuation allowance, Related Allowance	218	59
Impaired loans with a valuation allowance, Average Recorded Investment	321	79
Impaired loans with a valuation allowance, Interest Income Recognized	7	9
Purchased Credit Impaired Loans [Member] \| Consumer and Other [Member]
Financing Receivable, Impaired [Line Items]
Impaired loans with a valuation allowance, Recorded Investment	21	45
Impaired loans with a valuation allowance, Unpaid Principal Balance	20	51
Impaired loans with a valuation allowance, Related Allowance	3	6
Impaired loans with a valuation allowance, Average Recorded Investment	$ 27	9
Impaired loans with a valuation allowance, Interest Income Recognized		$ 1

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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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