Financing Arrangements and Debt (Narrative) (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Line of Credit Facility [Line Items]
Cost of debt extinguishment	$ 36,900,000
Early redemption of debt cost	34,177,000	$ 0
6.375% notes due July 2028
Line of Credit Facility [Line Items]
Debt instrument, face amount	$ 550,000,000
Stated interest rate	6.375%
Transaction costs	$ 8,000,000.0
4.00% notes due June 2022
Line of Credit Facility [Line Items]
Stated interest rate	4.00%
Repayments of debt	$ 259,300,000
4.95% notes due December 2022
Line of Credit Facility [Line Items]
Stated interest rate	4.95%
Repayments of debt	$ 317,100,000
3.70% notes due 2022
Line of Credit Facility [Line Items]
Stated interest rate	3.70%
2018 Revolving Credit Facility
Line of Credit Facility [Line Items]
Amount outstanding	$ 0
Interest rate	1.78%
2018 Revolving Credit Facility \| Letter of Credit
Line of Credit Facility [Line Items]
Credit facility maximum borrowing capacity	$ 1,600,000,000
Amount outstanding	$ 3,800,000

Cost Of Debt Extinguishment

No definition available.

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- Definition

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

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-Name Accounting Standards Codification
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- Definition

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

+ References

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- Definition

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

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- Definition

The effective interest rate during the reporting period.

+ References

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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.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

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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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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