Debt (Short-Term Debt And Current Portion Of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	$ 636.2		$ 495.4
Notes Payable to Bank, Current	85.0		270.8
Synthetic bonds due 2021
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	551.2		0.0
5.00% Notes due 2020 \| Unsecured debt
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	$ 0.0		$ 224.6
Debt Instrument, Interest Rate, Stated Percentage	5.00%	5.00%	5.00%

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Current portion of the total carrying amount as of the balance sheet date due within one year or the operating cycle, if longer, on all notes payable to banks paid on an installment with long term maturities. This can include the amount of any loans from the applicant firm. This does not, however, include any mortgage balances.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a)(1),20)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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