Long-Term Debt and Commercial Paper (Long-Term Debt) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Jan. 31, 2021	Dec. 31, 2020
Long-term debt	$ 1,812.8		$ 2,116.6
Less: unamortized debt discounts and debt issuance costs	(14.4)		(14.8)
Less: current maturities	(7.1)		(309.2)
Long-term debt, net of current maturities	$ 1,791.3		1,792.6
3.35% Senior Notes due 2021 [Member] \| Senior Notes [Member]
Percentage interest on debt instrument	3.35%	3.35%
Maturity date	Jan. 15, 2021
Senior notes	$ 0.0		300.0
3.5% Senior Notes Due 2024 [Member] \| Senior Notes [Member]
Percentage interest on debt instrument	3.50%
Maturity date	Nov. 15, 2024
Senior notes	$ 450.0		450.0
4.5% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Percentage interest on debt instrument	4.50%
Maturity date	Oct. 01, 2025
Senior notes	$ 450.0		450.0
3.8% Senior Notes Due 2027 [Member] \| Senior Notes [Member]
Percentage interest on debt instrument	3.80%
Maturity date	Nov. 15, 2027
Senior notes	$ 300.0		300.0
4.75% Senior Notes Due 2030 [Member] \| Senior Notes [Member]
Percentage interest on debt instrument	4.75%
Maturity date	Jun. 01, 2030
Senior notes	$ 500.0		500.0
Revolving Credit Facility Due 2025 [Member]
Revolving credit facility	$ 0.0		0.0
Revolving Credit Facility Due 2025 [Member] \| Line of Credit [Member]
Maturity date	Mar. 26, 2025
Other Debt [Member]
Other debt	$ 112.8		$ 116.6

Finance leases for real property and equipment classified as long-term debt.

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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- Definition

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

+ References

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

+ References

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Amount of long-term debt and lease obligation, classified as current.

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- Definition

Amount of long-term debt and lease obligation, including portion classified as current.

+ References

No definition available.

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