FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS: (Details 3) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Liabilities
Carrying value of Notes receivable	$ 6.4	$ 6.5
Principal carrying amount	2,222.0	2,751.8
2020 Unsecured Senior Notes
Liabilities
Fair Value	1,287.5	1,300.8
Principal carrying amount	1,250.0	1,250.0
Recurring basis \| Fair value
Assets
Cash equivalents	325.2	1,110.1
Government securities	0.3	0.3
Marketable equity securities		2.2
Total assets at fair value	325.5	1,112.6
Liabilities
Foreign exchange contracts	0.1
Interest rate swaps		4.8
Total liabilities at fair value	0.1	4.8
Recurring basis \| Level 1
Assets
Cash equivalents	325.2	1,110.1
Government securities	0.3	0.3
Marketable equity securities		2.2
Total assets at fair value	325.5	1,112.6
Liabilities
Foreign exchange contracts	0.1
Recurring basis \| Level 2
Liabilities
Interest rate swaps		4.8
Total liabilities at fair value	0.1	4.8
Recurring basis \| Level 3 \| Kemira
Liabilities
Fair value of notes receivable	$ 13.5	$ 13.8

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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