XML 55 R44.htm IDEA: XBRL DOCUMENT
v3.19.2

Leases - Additional Information (Detail) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2019 USD ($)
Leases [Line Items] |
Additional leases that have not yet commenced | $ 0.1
Maximum [Member] |
Leases [Line Items] |
Operating and finance leases, remaining lease terms | 12 years
Operating and finance leases, options to terminate leases term | 1 year
Minimum [Member] |
Leases [Line Items] |
Operating and finance leases, remaining lease terms | 1 year

X
- Definition Leases. + References No definition available. + Details
Name: | iosp_LeasesLineItems
Namespace Prefix: | iosp_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Lessee, operating and finance leases options to terminate leases term. + References No definition available. + Details
Name: | iosp_LesseeOperatingAndFinanceLeasesOptionsToTerminateLeasesTerm
Namespace Prefix: | iosp_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Lessee, operating and finance leases remaining lease term. + References No definition available. + Details
Name: | iosp_LesseeOperatingAndFinanceLeasesRemainingLeaseTerm
Namespace Prefix: | iosp_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition New leases not yet commenced. + References No definition available. + Details
Name: | iosp_NewLeasesNotYetCommenced
Namespace Prefix: | iosp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |