Loans Held for Investment - Schedule of Recorded Credit Quality Indicator (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Commitments to purchase or sell	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Proceeds from sale of loans held-for-investment	0.0	$ 0.0	0.0	$ 0.0
Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	697.5		697.5		$ 1,204.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,001.9		1,001.9		1,021.1
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	959.1		959.1		1,172.4
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,075.7		1,075.7		1,412.9
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,336.7		1,336.7		1,194.3
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	2,773.8		2,773.8		2,029.7
Financing Receivable, Excluding Accrued Interest, Revolving	61.9		61.9		59.6
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	41.3		41.3		49.5
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	7,947.9		7,947.9		8,144.4
Residential
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	18.0		18.0		46.0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	63.4		63.4		36.6
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	42.8		42.8		72.5
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	63.8		63.8		399.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	377.8		377.8		451.4
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	982.2		982.2		601.6
Financing Receivable, Excluding Accrued Interest, Revolving	492.5		492.5		494.3
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	4.2		4.2		7.4
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	2,044.7		2,044.7		2,108.8
Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	111.9		111.9		254.6
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	156.6		156.6		217.9
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	123.6		123.6		110.6
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	38.5		38.5		107.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	83.9		83.9		27.1
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	39.5		39.5		21.4
Financing Receivable, Excluding Accrued Interest, Revolving	18.2		18.2		86.1
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	3.9		3.9		12.5
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	576.1		576.1		837.2
Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	68.8		68.8		126.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	92.5		92.5		88.1
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	75.9		75.9		46.5
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	36.5		36.5		111.4
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	104.3		104.3		90.5
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	193.7		193.7		143.2
Financing Receivable, Excluding Accrued Interest, Revolving	20.4		20.4		21.8
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.6
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	592.1		592.1		629.0
Total real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	11,160.8		11,160.8		11,719.4
Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2.8		2.8		31.5
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	23.4		23.4		171.0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	131.5		131.5		75.7
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	56.7		56.7		103.1
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	79.6		79.6		40.5
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	75.0		75.0		55.7
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	369.0		369.0		477.5
Direct consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	22.8		22.8		47.8
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	35.4		35.4		25.8
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	19.2		19.2		13.4
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	9.5		9.5		10.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	6.9		6.9		5.3
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	8.0		8.0		5.1
Financing Receivable, Excluding Accrued Interest, Revolving	23.3		23.3		23.9
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.2		0.2		0.2
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	125.3		125.3		131.5
Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	494.3		494.3		609.0
Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	280.3		280.3		321.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	283.8		283.8		325.9
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	267.0		267.0		239.0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	183.9		183.9		299.1
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	252.3		252.3		233.8
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	361.1		361.1		261.5
Financing Receivable, Excluding Accrued Interest, Revolving	643.1		643.1		672.3
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	4.1		4.1		6.1
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	2,275.6		2,275.6		2,359.6
Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	51.5		51.5		97.6
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	48.3		48.3		30.0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	21.7		21.7		21.2
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	13.7		13.7		28.4
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	21.7		21.7		7.9
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	8.3		8.3		5.1
Financing Receivable, Excluding Accrued Interest, Revolving	186.3		186.3		315.4
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	5.8		5.8		14.6
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	357.3		357.3		520.2
Pass | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	615.2		615.2		1,025.6
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	888.1		888.1		948.6
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	926.4		926.4		1,095.2
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,012.1		1,012.1		1,344.8
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,250.0		1,250.0		1,101.6
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	2,577.6		2,577.6		1,892.9
Financing Receivable, Excluding Accrued Interest, Revolving	60.0		60.0		59.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	41.3		41.3		49.5
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	7,370.7		7,370.7		7,517.2
Pass | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	96.9		96.9		240.1
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	145.3		145.3		211.5
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	115.5		115.5		110.4
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	38.3		38.3		92.3
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	83.5		83.5		25.4
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	38.5		38.5		21.3
Financing Receivable, Excluding Accrued Interest, Revolving	18.2		18.2		85.9
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	3.9		3.9		12.5
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	540.1		540.1		799.4
Pass | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	44.9		44.9		100.8
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	87.6		87.6		68.5
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	59.6		59.6		36.5
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	32.0		32.0		104.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	97.8		97.8		73.7
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	166.2		166.2		121.6
Financing Receivable, Excluding Accrued Interest, Revolving	19.2		19.2		19.7
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	507.3		507.3		524.8
Pass | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	267.5		267.5		301.3
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	252.9		252.9		287.8
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	237.2		237.2		228.4
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	181.5		181.5		277.2
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	235.6		235.6		225.5
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	355.9		355.9		260.4
Financing Receivable, Excluding Accrued Interest, Revolving	595.4		595.4		593.3
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	2.9		2.9		4.6
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	2,128.9		2,128.9		2,178.5
Pass | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	31.3		31.3		80.2
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	38.9		38.9		25.0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	17.9		17.9		15.1
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	11.3		11.3		25.6
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	20.0		20.0		7.5
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	7.6		7.6		4.7
Financing Receivable, Excluding Accrued Interest, Revolving	157.5		157.5		277.8
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.3		0.3		5.6
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	284.8		284.8		441.5
Other Assets Especially Mentioned | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	22.8		22.8		96.3
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	55.4		55.4		28.9
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	20.8		20.8		43.7
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	32.9		32.9		35.4
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	62.5		62.5		64.6
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	100.9		100.9		88.4
Financing Receivable, Excluding Accrued Interest, Revolving	1.9		1.9		0.6
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	297.2		297.2		357.9
Other Assets Especially Mentioned | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.9		0.9		3.8
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	7.6		7.6		5.0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0.6		0.6		0.0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.0		0.0		14.4
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.1		0.1		0.0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	9.2		9.2		23.2
Other Assets Especially Mentioned | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2.5		2.5		10.2
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	2.2		2.2		10.1
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1.1		1.1		3.4
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	3.3		3.3		4.5
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1.8		1.8		8.7
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	10.1		10.1		13.8
Financing Receivable, Excluding Accrued Interest, Revolving	0.2		0.2		2.1
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	21.2		21.2		52.8
Other Assets Especially Mentioned | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	1.7		1.7		6.4
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4.3		4.3		23.7
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	23.9		23.9		3.3
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1.5		1.5		1.4
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	4.2		4.2		3.2
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1.6		1.6		0.4
Financing Receivable, Excluding Accrued Interest, Revolving	37.9		37.9		52.8
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.2
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	75.1		75.1		91.4
Other Assets Especially Mentioned | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2.6		2.6		7.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0.3		0.3		1.4
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0.9		0.9		2.7
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.5		0.5		2.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1.1		1.1		0.4
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.1		0.1		0.0
Financing Receivable, Excluding Accrued Interest, Revolving	12.5		12.5		26.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.1		0.1		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	18.1		18.1		40.4
Substandard | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	59.5		59.5		81.1
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	29.3		29.3		41.4
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	9.8		9.8		27.8
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	24.7		24.7		32.7
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	23.4		23.4		27.7
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	95.3		95.3		48.4
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	242.0		242.0		259.1
Substandard | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	14.1		14.1		10.7
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3.7		3.7		0.1
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	6.2		6.2		0.2
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.2		0.2		0.3
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.3		0.3		1.0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.3		0.3		0.1
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.2
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	24.8		24.8		12.6
Substandard | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	21.4		21.4		15.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	2.7		2.7		9.5
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	15.2		15.2		6.6
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1.2		1.2		2.9
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	4.7		4.7		8.1
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	17.4		17.4		7.8
Financing Receivable, Excluding Accrued Interest, Revolving	1.0		1.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.6
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	63.6		63.6		51.4
Substandard | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	11.1		11.1		9.3
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	5.6		5.6		13.4
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	5.6		5.6		6.8
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.9		0.9		14.2
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	8.8		8.8		4.7
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	3.6		3.6		0.7
Financing Receivable, Excluding Accrued Interest, Revolving	9.8		9.8		26.2
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	1.2		1.2		1.3
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	46.6		46.6		76.6
Substandard | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	17.6		17.6		3.3
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3.3		3.3		3.6
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	2.9		2.9		0.8
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1.9		1.9		0.8
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.6		0.6		0.0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.6		0.6		0.4
Financing Receivable, Excluding Accrued Interest, Revolving	16.3		16.3		9.6
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	5.4		5.4		1.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	48.6		48.6		19.5
Doubtful | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.0		0.0		1.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	29.1		29.1		2.2
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	2.1		2.1		5.7
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	6.0		6.0		0.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.8		0.8		0.4
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	38.0		38.0		10.2
Doubtful | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0.0		0.0		1.3
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1.3		1.3		0.0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.0		0.0		0.7
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.7		0.7		0.0
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	2.0		2.0		2.0
Doubtful | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.0		0.0		4.9
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	21.0		21.0		1.0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0.3		0.3		0.5
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.0		0.0		6.3
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3.7		3.7		0.4
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	25.0		25.0		13.1
Doubtful | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.0		0.0		6.2
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	5.8		5.8		0.0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0.0		0.0		2.6
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		2.0
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan	0.0		0.0		8.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	$ 5.8		$ 5.8		$ 18.8