Financing Receivable, Allowance for Credit Loss, Write-off, Net

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Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease), Percentage

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- Definition

Financing Receivable, Allowance for Credit Loss, Ratio

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- Definition

Forecasted Macroeconomic Variables, Percentage of Contraction, Gross Domestic Product In Current Fiscal Year

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- Definition

Forecasted Macroeconomic Variables, Percentage of Contraction, Gross Domestic Product In Next Fiscal Year

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- Definition

Forecasted Macroeconomic Variables, Percentage of Growth, Gross Domestic Product

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Forecasted Macroeconomic Variables, Percentage of Unemployment

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- Definition

Provision For Credit Losses

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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ALLOWANCE FOR CREDIT LOSSES ON LOANS AND LEASES - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
	Jan. 01, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Stockholders' equity attributable to parent		$ 4,974.0	$ 4,842.0	$ 4,959.0	$ 4,883.0
Financing receivable, allowance for credit loss, period increase (decrease)	$ 105.0			(1.1)
Allowance for credit loss		$ 362.0		$ 363.0
Percentage of growth, gross domestic product				4.00%
Percentage of unemployment		5.00%		6.00%
Percentage of contraction, gross domestic product, current year		6.00%
Percentage of contraction, gross domestic product, next fiscal year		2.00%
Financing receivable, allowance for credit loss, period increase (decrease), percentage				(0.30%)
Financing receivable, allowance for credit loss, ratio		1.42%		1.43%
Provision for credit losses		$ 5.9
Financing receivable, allowance for credit loss, write-off		7.1	5.7
Allowance For Credit Losses on Loans and Leases [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss		362.0	343.0	$ 363.0	196.0
Impact of ASC 326 Adoption [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Stockholders' equity attributable to parent			(50.0)
Retained Earnings [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Stockholders' equity attributable to parent		$ 921.0	754.0	$ 869.0	$ 798.0
Retained Earnings [Member] \| Impact of ASC 326 Adoption [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Stockholders' equity attributable to parent			$ (50.0)
Accounting Standards Update 2016-13 [Member] \| Retained Earnings [Member] \| Impact of ASC 326 Adoption [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Stockholders' equity attributable to parent	(50.6)
Longer Duration Loans and Gross Up [Member] \| Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, allowance for credit loss, period increase (decrease)	50.0
Unfunded Loan Commitment [Member] \| Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss	$ 10.0