INCOME TAXES INCOME TAXES (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Valuation Allowance [Abstract]
Valuation allowance	$ 16.6	$ 13.4	$ 21.1
Amount charged to income tax provision	4.1olin_Amountchargedtoincometaxprovision	4.9olin_Amountchargedtoincometaxprovision
Amount credited to income tax provision (i.e. deduction from reserve)	$ (0.9)	$ (12.6)

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Name:	us-gaap_DeferredTaxAssetsValuationAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant