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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
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Mar. 31, 2015 | Dec. 31, 2014
Income Tax Contingency [Line Items] |  |
Income tax examination, description | The Company and its U.S. subsidiaries remain open to examination by the IRS for years 2011 onwards. The Company's subsidiaries in foreign tax jurisdictions are open to examination including France (2013 onwards), Germany (2010 onwards), Switzerland (2013 onwards) and the United Kingdom (2013 onwards). |
Unremitted earnings |  | $ 743 iosp_UnremittedEarningOfForeignSubsidiary
France [Member] |  |
Income Tax Contingency [Line Items] |  |
Open tax year | 2013 |
Germany [Member] |  |
Income Tax Contingency [Line Items] |  |
Open tax year | 2010 |
Switzerland [Member] |  |
Income Tax Contingency [Line Items] |  |
Open tax year | 2013 |
United Kingdom [Member] |  |
Income Tax Contingency [Line Items] |  |
Open tax year | 2013 |

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- Definition A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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- Definition Tax year that remains open to examination under enacted tax laws, in CCYY format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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