DEBT AND BANK CREDIT FACILITIES (Details On The Senior Notes) (Details) $ in Millions	Mar. 31, 2018 USD ($)
Debt Instrument [Line Items]
Principal	$ 500.0
Senior Notes
Debt Instrument [Line Items]
Principal	500.0
Senior Notes \| Fixed Rate Series 2011A, Maturity 2018
Debt Instrument [Line Items]
Principal	$ 100.0
Debt instrument interest rate	4.10%
Senior Notes \| Fixed Rate Series 2011A, Maturity 2021
Debt Instrument [Line Items]
Principal	$ 230.0
Senior Notes \| Fixed Rate Series 2011A, Maturity 2021 \| Minimum
Debt Instrument [Line Items]
Debt instrument interest rate	4.80%
Senior Notes \| Fixed Rate Series 2011A, Maturity 2021 \| Maximum
Debt Instrument [Line Items]
Debt instrument interest rate	5.00%
Senior Notes \| Fixed Rate Series 2011A, Maturity 2023
Debt Instrument [Line Items]
Principal	$ 170.0
Senior Notes \| Fixed Rate Series 2011A, Maturity 2023 \| Minimum
Debt Instrument [Line Items]
Debt instrument interest rate	4.90%
Senior Notes \| Fixed Rate Series 2011A, Maturity 2023 \| Maximum
Debt Instrument [Line Items]
Debt instrument interest rate	5.10%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=6877327&loc=d3e13212-122682

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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