INCOME TAXES: (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
INCOME TAXES:
Unrecognized tax benefits	$ 20.5us-gaap_UnrecognizedTaxBenefits		$ 18.0us-gaap_UnrecognizedTaxBenefits
Total amount of accrued interest or penalties related to unrecognized tax benefit or tax contingencies	1.0		1.0
Effective tax rate (as a percent)	17.60%	(6.30%)
Tax at statutory rate (as a percent)	35.00%
Cash tax savings due to tax holiday	$ 6.1	$ 0.2
Increase in diluted earnings per share	$ 0.13	$ 0.01

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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-Publisher SEC

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Subparagraph (SAB TOPIC 6.I)

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

+ References

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-Publisher FASB

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-Paragraph 2

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Publisher FASB

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-Glossary Unrecognized Tax Benefit

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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