Loans Held for Investment - Schedule of Contractual Aging of Loans by Portfolio (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual loans	$ 55.5		$ 55.5		$ 59.8
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	14,281.4		14,281.4		15,201.6
Financing Receivable, Allowance for Credit Loss, Writeoff	14.0	$ 13.0	20.5	$ 23.8	55.0
Financing Receivable, Nonaccrual, Interest Income	(1.1)	(1.1)	(2.4)	(1.5)
Accrued interest reversal	(1.1)	(1.0)	(1.6)	(2.5)
Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	5.9		5.9		40.1
Nonaccrual loans	60.0		60.0		35.6
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, Allowance for Credit Loss, Writeoff			0.4		22.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	7,947.9		7,947.9		8,144.4
Commercial real estate | Pass
Loans and Leases Receivable, Troubled Debt Restructuring [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
Commercial real estate | Other Assets Especially Mentioned
Loans and Leases Receivable, Troubled Debt Restructuring [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
Commercial real estate | Substandard
Loans and Leases Receivable, Troubled Debt Restructuring [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
Commercial real estate | Doubtful
Loans and Leases Receivable, Troubled Debt Restructuring [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
Total construction loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.7		0.7		13.5
Nonaccrual loans	4.7		4.7		4.3
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
Total construction loans | Pass
Loans and Leases Receivable, Troubled Debt Restructuring [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
Total construction loans | Other Assets Especially Mentioned
Loans and Leases Receivable, Troubled Debt Restructuring [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
Total construction loans | Substandard
Loans and Leases Receivable, Troubled Debt Restructuring [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
Total construction loans | Doubtful
Loans and Leases Receivable, Troubled Debt Restructuring [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
Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	3.2		3.2		10.9
Nonaccrual loans	12.4		12.4		13.9
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, Allowance for Credit Loss, Writeoff			1.0		1.4
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	2,044.7		2,044.7		2,108.8
Residential | Performing Financial Instruments [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	17.9		17.9		45.6
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	62.9		62.9		35.5
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	41.8		41.8		71.5
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	62.7		62.7		394.6
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	374.8		374.8		449.2
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	975.4		975.4		596.8
Financing Receivable, Excluding Accrued Interest, Revolving	492.5		492.5		494.2
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	2,032.2		2,032.2		2,094.8
Residential | Nonperforming Financial Instruments [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.1		0.1		0.4
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0.5		0.5		1.1
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1.0		1.0		1.0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1.1		1.1		4.4
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3.0		3.0		2.2
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	6.8		6.8		4.8
Financing Receivable, Excluding Accrued Interest, Revolving	0.0		0.0		0.1
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	12.5		12.5		14.0
Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.3		0.3		0.2
Nonaccrual loans	21.6		21.6		27.1
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, Allowance for Credit Loss, Writeoff			0.1		0.2
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	592.1		592.1		629.0
Agricultural | Pass
Loans and Leases Receivable, Troubled Debt Restructuring [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
Agricultural | Other Assets Especially Mentioned
Loans and Leases Receivable, Troubled Debt Restructuring [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
Agricultural | Substandard
Loans and Leases Receivable, Troubled Debt Restructuring [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
Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	10.1		10.1		64.7
Nonaccrual loans	98.7		98.7		80.9
Financing Receivable, Allowance for Credit Loss, Writeoff	1.0	3.2	1.5	3.5	23.6
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, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	5.3		5.3		8.3
Nonaccrual loans	4.1		4.1		5.6
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, Allowance for Credit Loss, Writeoff			4.0		9.6
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	369.0		369.0		477.5
Indirect consumer | Performing Financial Instruments [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2.8		2.8		30.8
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	22.8		22.8		169.6
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	130.5		130.5		74.5
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	55.9		55.9		102.1
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	78.8		78.8		39.9
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	74.0		74.0		54.9
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	364.8		364.8		471.8
Indirect consumer | Nonperforming Financial Instruments [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.0		0.0		0.7
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0.6		0.6		1.4
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1.0		1.0		1.2
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.8		0.8		1.0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0.8		0.8		0.6
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1.0		1.0		0.8
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	4.2		4.2		5.7
Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	6.4		6.4		9.4
Nonaccrual loans	4.8		4.8		6.3
Financing Receivable, Allowance for Credit Loss, Writeoff	2.4	5.6	6.2	10.3	17.5
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, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	6.6		6.6		8.9
Nonaccrual loans	37.1		37.1		21.7
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, Allowance for Credit Loss, Writeoff	2.1	2.2	4.3	5.1	8.9
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	2,275.6		2,275.6		2,359.6
Commercial | Pass
Loans and Leases Receivable, Troubled Debt Restructuring [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
Commercial | Other Assets Especially Mentioned
Loans and Leases Receivable, Troubled Debt Restructuring [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
Commercial | Substandard
Loans and Leases Receivable, Troubled Debt Restructuring [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
Commercial | Doubtful
Loans and Leases Receivable, Troubled Debt Restructuring [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
Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	2.5		2.5		1.1
Nonaccrual loans	17.8		17.8		24.6
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, Allowance for Credit Loss, Writeoff	8.5	$ 2.0	8.5	$ 4.9	5.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	357.3		357.3		520.2
Agricultural | Pass
Loans and Leases Receivable, Troubled Debt Restructuring [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
Agricultural | Other Assets Especially Mentioned
Loans and Leases Receivable, Troubled Debt Restructuring [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
Agricultural | Substandard
Loans and Leases Receivable, Troubled Debt Restructuring [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
Agricultural | Doubtful
Loans and Leases Receivable, Troubled Debt Restructuring [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
Other, including overdrafts
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
Nonaccrual loans	0.0		0.0		0.0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	1.4		1.4		1.7
Loans And Leases Held For Investment [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	25.6		25.6		84.1
Nonaccrual loans	158.4		158.4		133.5
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	14,289.4		14,289.4		15,209.9
Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.1		1.1		1.1
Nonaccrual loans	0.7		0.7		0.7
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, Allowance for Credit Loss, Writeoff			2.2		4.4
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	125.3		125.3		131.5
Consumer Loan | Performing Financial Instruments [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	22.7		22.7		47.7
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	35.3		35.3		25.6
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	19.0		19.0		13.3
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	9.4		9.4		9.9
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	6.8		6.8		5.3
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	7.9		7.9		5.0
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		0.1
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	124.6		124.6		130.8
Consumer Loan | Nonperforming Financial Instruments [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0.1		0.1		0.1
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0.1		0.1		0.2
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0.2		0.2		0.1
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0.1		0.1		0.1
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	0.1		0.1		0.1
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		0.1
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process	0.7		0.7		0.7
Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					3.5
30 to 59 Days Past Due
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual loans	1.8		1.8		4.5
30 to 59 Days Past Due | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	5.2		5.2		34.1
30 to 59 Days Past Due | Total construction loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.5		0.5		13.4
30 to 59 Days Past Due | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.8		1.8		8.3
30 to 59 Days Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.2		0.2		0.2
30 to 59 Days Past Due | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	7.7		7.7		56.0
30 to 59 Days Past Due | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	3.9		3.9		6.5
30 to 59 Days Past Due | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	4.7		4.7		7.4
30 to 59 Days Past Due | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	3.2		3.2		3.1
30 to 59 Days Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	2.3		2.3		0.5
30 to 59 Days Past Due | Other, including overdrafts
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
30 to 59 Days Past Due | Loans And Leases Held For Investment [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	17.9		17.9		67.0
30 to 59 Days Past Due | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.8		0.8		0.9
60 to 89 Days Past Due
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual loans	3.6		3.6		3.8
60 to 89 Days Past Due | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.7		0.7		5.7
60 to 89 Days Past Due | Total construction loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.2		0.2		0.1
60 to 89 Days Past Due | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.3		1.3		2.5
60 to 89 Days Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.1		0.1		0.0
60 to 89 Days Past Due | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	2.3		2.3		8.3
60 to 89 Days Past Due | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.3		1.3		1.7
60 to 89 Days Past Due | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.6		1.6		1.9
60 to 89 Days Past Due | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	2.3		2.3		4.9
60 to 89 Days Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.2		0.2		0.6
60 to 89 Days Past Due | Other, including overdrafts
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
60 to 89 Days Past Due | Loans And Leases Held For Investment [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	6.4		6.4		15.7
60 to 89 Days Past Due | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.3		0.3		0.2
Equal to or Greater than 90 Days Past Due
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual loans	97.1		97.1		60.5
Equal to or Greater than 90 Days Past Due | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.3
Equal to or Greater than 90 Days Past Due | Total construction loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
Equal to or Greater than 90 Days Past Due | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.1		0.1		0.1
Equal to or Greater than 90 Days Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
Equal to or Greater than 90 Days Past Due | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.1		0.1		0.4
Equal to or Greater than 90 Days Past Due | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.1		0.1		0.1
Equal to or Greater than 90 Days Past Due | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.1		0.1		0.1
Equal to or Greater than 90 Days Past Due | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.1		1.1		0.9
Equal to or Greater than 90 Days Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
Equal to or Greater than 90 Days Past Due | Other, including overdrafts
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
Equal to or Greater than 90 Days Past Due | Loans And Leases Held For Investment [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.3		1.3		1.4
Equal to or Greater than 90 Days Past Due | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	0.0		0.0		0.0
Financial Asset, Not Past Due | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	7,882.0		7,882.0		8,068.7
Financial Asset, Not Past Due | Total construction loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	570.7		570.7		819.4
Financial Asset, Not Past Due | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	2,029.1		2,029.1		2,084.0
Financial Asset, Not Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	570.2		570.2		601.7
Financial Asset, Not Past Due | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	11,052.0		11,052.0		11,573.8
Financial Asset, Not Past Due | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	359.6		359.6		463.6
Financial Asset, Not Past Due | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	483.1		483.1		593.3
Financial Asset, Not Past Due | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	2,231.9		2,231.9		2,329.0
Financial Asset, Not Past Due | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	337.0		337.0		494.5
Financial Asset, Not Past Due | Other, including overdrafts
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	1.4		1.4		1.7
Financial Asset, Not Past Due | Loans And Leases Held For Investment [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	14,105.4		14,105.4		14,992.3
Financial Asset, Not Past Due | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Loan in Process	$ 123.5		123.5		129.7
Year One, Originated, Current Fiscal Year
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.2		3.8
Year One, Originated, Current Fiscal Year | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year One, Originated, Current Fiscal Year | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.1
Year One, Originated, Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year One, Originated, Current Fiscal Year | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.1
Year One, Originated, Current Fiscal Year | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.6
Year One, Originated, Current Fiscal Year | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		1.0
Year One, Originated, Current Fiscal Year | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.2		0.7
Year One, Originated, Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		2.0
Year One, Originated, Current Fiscal Year | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.4
Year One, Originated, Current Fiscal Year | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					0.0
Year Two, Originated, Fiscal Year Before Current Fiscal Year
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			8.6		8.4
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.4
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.5
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.2		0.9
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.7		2.4
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.2		3.6
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.7		1.0
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			6.5		2.9
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.5		1.2
Year Two, Originated, Fiscal Year Before Current Fiscal Year | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					0.0
Year Three, Originated, Two Years before Current Fiscal Year
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			2.4		5.9
Year Three, Originated, Two Years before Current Fiscal Year | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.1
Year Three, Originated, Two Years before Current Fiscal Year | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.1
Year Three, Originated, Two Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.2
Year Three, Originated, Two Years before Current Fiscal Year | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.4
Year Three, Originated, Two Years before Current Fiscal Year | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.2		2.4
Year Three, Originated, Two Years before Current Fiscal Year | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.5		3.0
Year Three, Originated, Two Years before Current Fiscal Year | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.8		2.5
Year Three, Originated, Two Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year Three, Originated, Two Years before Current Fiscal Year | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.3		0.6
Year Three, Originated, Two Years before Current Fiscal Year | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					0.0
Year Four, Originated, Three Years before Current Fiscal Year
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.8		20.5
Year Four, Originated, Three Years before Current Fiscal Year | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		16.2
Year Four, Originated, Three Years before Current Fiscal Year | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.4		0.4
Year Four, Originated, Three Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year Four, Originated, Three Years before Current Fiscal Year | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.4		16.6
Year Four, Originated, Three Years before Current Fiscal Year | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.6		2.4
Year Four, Originated, Three Years before Current Fiscal Year | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.9		2.6
Year Four, Originated, Three Years before Current Fiscal Year | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.5		1.3
Year Four, Originated, Three Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year Four, Originated, Three Years before Current Fiscal Year | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.3		0.2
Year Four, Originated, Three Years before Current Fiscal Year | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					0.0
Year Five, Originated, Four Years before Current Fiscal Year
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.3		6.5
Year Five, Originated, Four Years before Current Fiscal Year | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		5.1
Year Five, Originated, Four Years before Current Fiscal Year | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.3		0.2
Year Five, Originated, Four Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year Five, Originated, Four Years before Current Fiscal Year | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.3		5.3
Year Five, Originated, Four Years before Current Fiscal Year | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.7		0.8
Year Five, Originated, Four Years before Current Fiscal Year | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.8		0.9
Year Five, Originated, Four Years before Current Fiscal Year | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.2		0.3
Year Five, Originated, Four Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Year Five, Originated, Four Years before Current Fiscal Year | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.1
Year Five, Originated, Four Years before Current Fiscal Year | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					0.0
Originated, More than Five Years before Current Fiscal Year
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			2.6		3.6
Originated, More than Five Years before Current Fiscal Year | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.3		0.2
Originated, More than Five Years before Current Fiscal Year | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.1
Originated, More than Five Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Originated, More than Five Years before Current Fiscal Year | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.4		0.3
Originated, More than Five Years before Current Fiscal Year | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.8		1.0
Originated, More than Five Years before Current Fiscal Year | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.7		2.9
Originated, More than Five Years before Current Fiscal Year | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.5		0.4
Originated, More than Five Years before Current Fiscal Year | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Originated, More than Five Years before Current Fiscal Year | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.9		1.9
Originated, More than Five Years before Current Fiscal Year | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					0.0
Revolving
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.4		6.1
Revolving | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.0
Revolving | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.0
Revolving | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		3.5
Revolving | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			1.3		2.5
Revolving | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.1
Revolving | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					3.5
Revolving, Converted to Term
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			2.2		0.2
Revolving, Converted to Term | Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving, Converted to Term | Residential
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving, Converted to Term | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving, Converted to Term | Total real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving, Converted to Term | Indirect consumer
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.0		0.0
Revolving, Converted to Term | Total consumer loans
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.0
Revolving, Converted to Term | Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			0.1		0.2
Revolving, Converted to Term | Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			2.0		0.0
Revolving, Converted to Term | Consumer Loan
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff			$ 0.1		0.0
Revolving, Converted to Term | Credit Card Receivable [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff					$ 0.0