Loans - Schedule of Financing Receivables Credit Quality Indicators (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Total
Total	$ 8,481,310		$ 8,314,096
Agricultural Finance
Year One
Total	407,133		2,224,509
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Two
Total	2,207,958		1,596,563
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Three
Total	1,537,824		617,576
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Four
Total	571,198		400,104
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Five
Total	372,486		351,687
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Prior
Total	1,295,289		1,095,135
Current period charge-offs	(84)		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	(84)		0
Revolving Loans - Amortized Cost Basis
Total	540,341		561,419
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Total
Total	6,932,229		6,846,993
Current period charge-offs	(84)	$ 0	0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	(84)		0
Rural Infrastructure Finance
Year One
Total	175,976		242,570
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Two
Total	230,729		635,166
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Three
Total	643,667		774,941
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Four
Total	766,559		8,100
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Year Five
Total	8,017		86,878
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Prior
Total	695,266		628,903
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Revolving Loans - Amortized Cost Basis
Total	31,637		12,578
Current period charge-offs	0		0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Total
Total	2,551,851		2,389,136
Current period charge-offs	0	$ 0	0
Current period recoveries	0		0
Current period Agricultural Finance net charge-offs	0		0
Acceptable | Agricultural Finance
Year One
Total	400,124		2,138,060
Year Two
Total	2,080,013		1,541,509
Year Three
Total	1,473,300		540,139
Year Four
Total	504,767		324,917
Year Five
Total	306,332		303,852
Prior
Total	1,179,889		1,004,709
Revolving Loans - Amortized Cost Basis
Total	512,678		545,370
Total
Total	6,457,103		6,398,556
Acceptable | Rural Infrastructure Finance
Year One
Total	175,976		242,570
Year Two
Total	230,729		612,366
Year Three
Total	643,667		774,941
Year Four
Total	766,559		8,100
Year Five
Total	8,017		86,878
Prior
Total	695,266		628,903
Revolving Loans - Amortized Cost Basis
Total	31,637		12,578
Total
Total	2,551,851		2,366,336
Special mention | Agricultural Finance
Year One
Total	7,009		84,795
Year Two
Total	123,893		50,057
Year Three
Total	38,473		51,200
Year Four
Total	43,697		48,078
Year Five
Total	45,722		9,132
Prior
Total	25,750		14,646
Revolving Loans - Amortized Cost Basis
Total	9,279		4,771
Total
Total	293,823		262,679
Special mention | Rural Infrastructure Finance
Year One
Total	0		0
Year Two
Total	0		0
Year Three
Total	0		0
Year Four
Total	0		0
Year Five
Total	0		0
Prior
Total	0		0
Revolving Loans - Amortized Cost Basis
Total	0		0
Total
Total	0		0
Substandard | Agricultural Finance
Year One
Total	0		1,654
Year Two
Total	4,052		4,997
Year Three
Total	26,051		26,237
Year Four
Total	22,734		27,109
Year Five
Total	20,432		38,703
Prior
Total	89,650		75,780
Revolving Loans - Amortized Cost Basis
Total	18,384		11,278
Total
Total	181,303		185,758
Substandard | Rural Infrastructure Finance
Year One
Total	0		0
Year Two
Total	0		22,800
Year Three
Total	0		0
Year Four
Total	0		0
Year Five
Total	0		0
Prior
Total	0		0
Revolving Loans - Amortized Cost Basis
Total	0		0
Total
Total	$ 0		$ 22,800