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

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Amount, after accumulated amortization, of debt discount.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Debt and Credit Agreements Debt Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 25, 2021
Schedule of New Debt Issuance [Line Items]
Loss on Extinguishment of Debt	$ (74.0)	$ 0.0	$ 0.0
Recognition of previously unrealized losses included in net income	(4.2)	$ (2.4)	$ (2.3)
3.75% Notes Due 2021
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	500.0
4.00% Notes Due 2022
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	250.0
Payment for Debt Extinguishment or Debt Prepayment Cost	258.9
Loss on Extinguishment of Debt	9.2
Redemption Premium	8.6
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0.6
3.75% Notes Due 2023
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	500.0
Payment for Debt Extinguishment or Debt Prepayment Cost	532.9
Loss on Extinguishment of Debt	36.5
Redemption Premium	30.7
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	1.1
Recognition of previously unrealized losses included in net income	4.7
4.20% Notes Due 2024
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	250.0
Debt instrument, unamortized discount	0.1
Payment for Debt Extinguishment or Debt Prepayment Cost	282.2
Loss on Extinguishment of Debt	28.3
Redemption Premium	27.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	0.8
4.65% Notes Due 2028
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	500.0
Debt instrument, unamortized discount	1.2
4.75% Note Due 2030
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	650.0
Debt instrument, unamortized discount	3.2
5.40% Notes Due 2048
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	500.0
Debt instrument, unamortized discount	2.7
2.400% Note Due 2031 (less unamortized discount and issuance costs of $0.7 and $4.3, respectively)
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	500.0
Unsecured Debt				$ 494.5
Debt instrument, unamortized discount	0.7			0.8
Debt Issuance Costs, Gross				4.7
3.375% Note Due 2041 (less unamortized discount and issuance costs of $1.1 and $5.5, respectively)
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	500.0
Unsecured Debt				493.1
Debt instrument, unamortized discount	1.1			1.1
Debt Issuance Costs, Gross				$ 5.8
Unsecured Debt 4.200% Notes Original Principal
Schedule of New Debt Issuance [Line Items]
Debt Instrument, Face Amount	$ 500.0