Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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- Definition

Gross amount of debt extinguished.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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DEBT AND CREDIT AGREEMENTS (Issuances and Redemptions) (Details) - USD ($)	1 Months Ended
	Aug. 31, 2021	May 31, 2021	Sep. 30, 2020	Apr. 30, 2020	Dec. 31, 2021	Aug. 31, 2020
Line of Credit \| 2019 Credit Agreement
Debt Instrument [Line Items]
Redemption of debt				$ 225,000,000
Debt extinguishment				225,000,000
2021 Senior Notes \| Unsecured Debt
Debt Instrument [Line Items]
Interest rate		3.25%			3.25%
Debt instrument, face amount		$ 325,000,000
Proceeds from issuance of debt		$ 325,000,000
Fixed Rate Tax-exempt Bonds Maturing in October 2020
Debt Instrument [Line Items]
Redemption of debt			$ 80,000,000
Debt extinguishment			80,000,000
Fixed rate tax-exempt bonds callable for redemption at par on or after October 2020
Debt Instrument [Line Items]
Redemption of debt			100,000,000
Debt extinguishment			$ 100,000,000
2020 Senior Notes \| Unsecured Debt
Debt Instrument [Line Items]
Interest rate					1.50%
Debt instrument, face amount						$ 300,000,000
2020 Senior Notes \| Unsecured Debt
Debt Instrument [Line Items]
Interest rate					4.00%
Debt instrument, face amount				$ 350,000,000
2011 Senior Notes \| Unsecured Debt
Debt Instrument [Line Items]
Redemption of debt	$ 250,000,000
Interest rate	5.15%				5.15%
Debt extinguishment	$ 250,000,000