Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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The increase (decrease) during the reporting period in outstanding loans including accrued interest.

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Amount of expense related to estimated loss from loan and lease transactions.

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Amount of reduction to fair value of loan related to real estate owned (REO) at time of acquisition.

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Loans - Allowance for Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for losses	$ 14,939	$ 14,939			$ 10,454
Provision to allowance for loan losses	500
Real estate owned, amount of loss at acquisition	400
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for losses				$ 2,656
Farm & Ranch
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for losses	6,039	6,039	$ 7,353		10,454
Farm & Ranch \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for losses			0	(3,909)	(3,909)
Rural Utilities
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for losses	8,900	8,900	7,503		0
Provision to allowance for loan losses		$ 3,400
Increase (decrease) in loan volume	$ 311,800
Rural Utilities \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for losses			$ 0	$ 5,378	$ 5,378