Amount of allowance for credit loss on accounts receivable.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of allowance for credit losses related to recorded investment.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense related to estimated loss from loan and lease transactions.

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Loans - Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	$ 4.3		$ 4.3			$ 0.3
Impaired Financing Receivable, Related Allowance						3.6
Provision charged to operating expense	(5.2)	$ (2.6)	(53.7)	$ (10.1)
Accounts Receivable, Allowance for Credit Loss	145.5	$ 75.0	145.5	$ 75.0	$ 146.1	73.0	$ 74.2	$ 73.0
Collateral dependent borrowings	16.0		16.0
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	4.0
Balance of defaulted loans under trouble debt restructurings	0.0		0.0
Agriculture Portfolio Segment [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	0.0
Accounts Receivable, Allowance for Credit Loss	0.9		0.9		0.9
Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	(3.2)		(21.3)
Accounts Receivable, Allowance for Credit Loss	78.6		78.6		75.2	28.9
Collateral dependent borrowings	0.7		0.7
Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	(1.1)		(23.8)
Accounts Receivable, Allowance for Credit Loss	42.0		42.0		46.5	32.6
Collateral dependent borrowings	15.2		15.2
Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	0.0		0.0
Accounts Receivable, Allowance for Credit Loss	0.9		0.9		$ 0.9	$ 1.6
Collateral dependent borrowings	0.1		0.1
Business Assets Pledged as Collateral [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	10.0		10.0
Business Assets Pledged as Collateral [Member] \| Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.2		0.2
Business Assets Pledged as Collateral [Member] \| Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	9.8		9.8
Business Assets Pledged as Collateral [Member] \| Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.0		0.0
Real Property Pledged as Collateral [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	5.6		5.6
Real Property Pledged as Collateral [Member] \| Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.5		0.5
Real Property Pledged as Collateral [Member] \| Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	5.0		5.0
Real Property Pledged as Collateral [Member] \| Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.1		0.1
Other Property [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.4		0.4
Other Property [Member] \| Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.0		0.0
Other Property [Member] \| Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.4		0.4
Other Property [Member] \| Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	$ 0.0		$ 0.0