XML 70 R59.htm IDEA: XBRL DOCUMENT v3.5.0.2

Stock-Based Compensation Plans - Fair Value of Liability Cash-Settled Long-Term Incentives (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Balance at January 1	$ 1.0	$ 0.1
Compensation charge for the period	0.6	0.4
Balance at September 30	$ 1.6	$ 0.5

X

- Definition

Change in fair value of liability cash-settled stock appreciation rights.

+ References

No definition available.

+ Details

Name:	iosp_ChangeInFairValueOfLiabilityCashSettledStockAppreciationRights
Namespace Prefix:	iosp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Fair value of liability cash-settled stock appreciation rights.

+ References

No definition available.

+ Details

Name:	iosp_FairValueOfLiabilityCashSettledStockAppreciationRights
Namespace Prefix:	iosp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- References

No definition available.

+ Details

Name:	us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration