Loans and Related Allowance for Loan Losses (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	$ 1,058,323	$ 993,705
Purchased credit impaired (PCI) loans	32,528	38,285
Allowance for loan losses	8,429	8,983
Interest income recognized on impaired loans	248	430
Estimated interest income	$ 345	$ 634
Number of TDR loans \| loan	24	25
Number of TDR loans defaulted \| loan	1	0
Total impaired	$ 9,885	$ 17,859
1-4 family mortgages pledged as collateral to the Federal Bank Home Loan	107,000
Total borrowing capacity	90,400
Provision For Loan And Lease Losses	325
Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Pre-modification balance		2,600
Post-modification balance		2,600
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Pre-modification balance		126
Post-modification balance		126
Commercial Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Pre-modification balance		233
Post-modification balance		233
Guaranteed Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	$ 12,700	17,400
Percentage of loans guaranteed by the USDA	100.00%
Unamortized purchase premium	$ 1,000	1,200
Mortgage Loans on Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	854,925	791,290
Interest income recognized on impaired loans	232	411
Total impaired	9,424	15,876
Mortgage Loans on Real Estate [Member] \| Residential 1-4 Family [Member]
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	223,538	216,268
Interest income recognized on impaired loans	87	124
Total impaired	2,981	3,694
Mortgage Loans on Real Estate [Member] \| Agriculture [Member]
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	8,346	8,370
Mortgage Loans on Real Estate [Member] \| Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	72,978	59,557
Interest income recognized on impaired loans		123
Total impaired	2,463	2,559
Recorded investment	2,500
Mortgage Loans on Real Estate [Member] \| Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Purchased government-guaranteed loans	396,858	379,904
Interest income recognized on impaired loans	145	164
Total impaired	$ 3,604	$ 5,052
Pass [Member] \| Guaranteed Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of loans guaranteed by the USDA	100.00%	100.00%
Purchased government-guaranteed loans	$ 12,700	$ 17,400

Percentage of loans guaranteed by USDA.

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Purchased government guaranteed loans.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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