Loans - Schedule of Impaired Financing Receivables (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2020
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	$ 52,191
Impaired loans, with no specific allowance, unpaid principal balance	52,014
Impaired loan, with a specific allowance, recorded investment	174,385
Impaired loans, with a specific allowance, unpaid principal balance	173,844
Impaired loans, associated allowance	6,541
Recorded investment	226,576
Unpaid principal balance	225,858
Recorded investment of loans on nonaccrual status	87,781	$ 114,998
Average recorded investment in impaired loans	190,106
Income recognized on impaired loans	2,753
Less than 90 days past due
Financing Receivable, Impaired [Line Items]
Recorded investment of loans on nonaccrual status	30,100
Crops
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	30,846
Impaired loans, with no specific allowance, unpaid principal balance	30,741
Impaired loan, with a specific allowance, recorded investment	84,044
Impaired loans, with a specific allowance, unpaid principal balance	83,772
Impaired loans, associated allowance	2,725
Recorded investment	114,890
Unpaid principal balance	114,513
Recorded investment of loans on nonaccrual status	34,037
Average recorded investment in impaired loans	101,053
Income recognized on impaired loans	1,157
Permanent Plantings
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	16,696
Impaired loans, with no specific allowance, unpaid principal balance	16,638
Impaired loan, with a specific allowance, recorded investment	36,852
Impaired loans, with a specific allowance, unpaid principal balance	36,732
Impaired loans, associated allowance	1,051
Recorded investment	53,548
Unpaid principal balance	53,370
Recorded investment of loans on nonaccrual status	22,849
Average recorded investment in impaired loans	44,986
Income recognized on impaired loans	625
Livestock
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	3,195
Impaired loans, with no specific allowance, unpaid principal balance	3,185
Impaired loan, with a specific allowance, recorded investment	47,113
Impaired loans, with a specific allowance, unpaid principal balance	46,984
Impaired loans, associated allowance	2,636
Recorded investment	50,308
Unpaid principal balance	50,169
Recorded investment of loans on nonaccrual status	28,441
Average recorded investment in impaired loans	36,054
Income recognized on impaired loans	687
Part-time Farm
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	1,398
Impaired loans, with no specific allowance, unpaid principal balance	1,394
Impaired loan, with a specific allowance, recorded investment	6,376
Impaired loans, with a specific allowance, unpaid principal balance	6,356
Impaired loans, associated allowance	129
Recorded investment	7,774
Unpaid principal balance	7,750
Recorded investment of loans on nonaccrual status	2,454
Average recorded investment in impaired loans	7,953
Income recognized on impaired loans	284
Ag. Storage and Processing
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	0
Impaired loans, with no specific allowance, unpaid principal balance	0
Impaired loan, with a specific allowance, recorded investment	0
Impaired loans, with a specific allowance, unpaid principal balance	0
Impaired loans, associated allowance	0
Recorded investment	0
Unpaid principal balance	0
Recorded investment of loans on nonaccrual status	0
Average recorded investment in impaired loans	0
Income recognized on impaired loans	0
Other
Financing Receivable, Impaired [Line Items]
Impaired loans, with no specific allowance, recorded investment	56
Impaired loans, with no specific allowance, unpaid principal balance	56
Impaired loan, with a specific allowance, recorded investment	0
Impaired loans, with a specific allowance, unpaid principal balance	0
Impaired loans, associated allowance	0
Recorded investment	56
Unpaid principal balance	56
Recorded investment of loans on nonaccrual status	0
Average recorded investment in impaired loans	60
Income recognized on impaired loans	0
Collateral Dependent Not Individually Analyzed
Financing Receivable, Impaired [Line Items]
Impaired loans, associated allowance	3,000
Recorded investment	$ 159,100
Impaired loans, impairment analysis performed percent	70.00%