Loans and Allowance for Losses - Schedule of Impaired Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	$ 57,414		$ 32,012
Impaired Loans, With so specific allowance, Unpaid principal balance	57,292		31,854
Impaired Loan, With a specific allowance, Recorded investment	117,404		123,300
Impaired Loans, With a specific allowance, Unpaid principal balance	117,189		122,786
Impaired Loans, Associated allowance	3,326		3,405
Recorded investment	174,818		155,312
Unpaid principal balance	174,481		154,640
Recorded investment of loans on nonaccrual status	62,972		61,408
Average recorded investment in impaired loans	165,066	$ 147,284
Income recognized on impaired loans	801	698
Crops [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	32,570		20,734
Impaired Loans, With so specific allowance, Unpaid principal balance	32,501		20,632
Impaired Loan, With a specific allowance, Recorded investment	64,666		59,335
Impaired Loans, With a specific allowance, Unpaid principal balance	64,550		59,098
Impaired Loans, Associated allowance	1,750		1,606
Recorded investment	97,236		80,069
Unpaid principal balance	97,051		79,730
Recorded investment of loans on nonaccrual status	35,879		26,611
Average recorded investment in impaired loans	88,653	72,017
Income recognized on impaired loans	322	392
Permanent Plantings [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	15,531		3,592
Impaired Loans, With so specific allowance, Unpaid principal balance	15,498		3,573
Impaired Loan, With a specific allowance, Recorded investment	23,690		38,176
Impaired Loans, With a specific allowance, Unpaid principal balance	23,644		38,009
Impaired Loans, Associated allowance	868		1,134
Recorded investment	39,221		41,768
Unpaid principal balance	39,142		41,582
Recorded investment of loans on nonaccrual status	12,843		21,349
Average recorded investment in impaired loans	40,495	43,427
Income recognized on impaired loans	299	172
Livestock [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	7,708		5,764
Impaired Loans, With so specific allowance, Unpaid principal balance	7,691		5,737
Impaired Loan, With a specific allowance, Recorded investment	23,331		19,443
Impaired Loans, With a specific allowance, Unpaid principal balance	23,289		19,361
Impaired Loans, Associated allowance	585		522
Recorded investment	31,039		25,207
Unpaid principal balance	30,980		25,098
Recorded investment of loans on nonaccrual status	10,490		8,803
Average recorded investment in impaired loans	28,123	22,274
Income recognized on impaired loans	113	79
Part-Time Farm [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	1,605		1,922
Impaired Loans, With so specific allowance, Unpaid principal balance	1,602		1,912
Impaired Loan, With a specific allowance, Recorded investment	5,657		6,276
Impaired Loans, With a specific allowance, Unpaid principal balance	5,646		6,249
Impaired Loans, Associated allowance	122		142
Recorded investment	7,262		8,198
Unpaid principal balance	7,248		8,161
Recorded investment of loans on nonaccrual status	3,760		4,645
Average recorded investment in impaired loans	7,730	8,850
Income recognized on impaired loans	67	55
Agriculture Storage and Processing [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	0		0
Impaired Loans, With so specific allowance, Unpaid principal balance	0		0
Impaired Loan, With a specific allowance, Recorded investment	0		0
Impaired Loans, With a specific allowance, Unpaid principal balance	0		0
Impaired Loans, Associated allowance	0		0
Recorded investment	0		0
Unpaid principal balance	0		0
Recorded investment of loans on nonaccrual status	0		0
Average recorded investment in impaired loans	0	0
Income recognized on impaired loans	0	0
Other Commodity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, With so specific allowance, Recorded investment	0		0
Impaired Loans, With so specific allowance, Unpaid principal balance	0		0
Impaired Loan, With a specific allowance, Recorded investment	60		70
Impaired Loans, With a specific allowance, Unpaid principal balance	60		69
Impaired Loans, Associated allowance	1		1
Recorded investment	60		70
Unpaid principal balance	60		69
Recorded investment of loans on nonaccrual status	0		0
Average recorded investment in impaired loans	65	716
Income recognized on impaired loans	0	$ 0
Collateral Dependent Not Individually Analyzed [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans, Associated allowance	2,500		2,700
Recorded investment	$ 115,000		$ 120,900
Impaired loans, impairment analysis performed percent	66.00%		78.00%
Less than 90 days past due [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment of loans on nonaccrual status	$ 15,800		$ 41,800

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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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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-Publisher FASB
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