XML 427 R185.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Retirement benefits - Defined Benefit Plans - Life Expectancy Assumptions at Retirement Age (Detail) - Pension plans [member] - yr | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
United Kingdom [member] |  |  |
Disclosure Of Forecast Life Expectancies [line items] |  |  |
Current pensioners at 65 - male | 24 | 24 | 24
Current pensioners at 65 - female | 26 | 26 | 26
Future pensioners at 65 - male | 25 | 25 | 25
Future pensioners at 65 - female | 28 | 28 | 28
United States [member] |  |  |
Disclosure Of Forecast Life Expectancies [line items] |  |  |
Current pensioners at 65 - male | 21 | 21 | 21
Current pensioners at 65 - female | 23 | 23 | 23
Future pensioners at 65 - male | 22 | 22 | 22
Future pensioners at 65 - female | 24 | 24 | 24

X
- Definition Disclosure Of Forecast Life Expectancies [line items] + References No definition available. + Details
Name: | ihg_DisclosureOfForecastLifeExpectanciesLineItems
Namespace Prefix: | ihg_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Longevity for current pensioners, females. + References No definition available. + Details
Name: | ihg_LongevityForCurrentPensionersFemales
Namespace Prefix: | ihg_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Longevity for current pensioners, males. + References No definition available. + Details
Name: | ihg_LongevityForCurrentPensionersMales
Namespace Prefix: | ihg_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Longevity for future pensioners, females. + References No definition available. + Details
Name: | ihg_LongevityForFuturePensionersFemales
Namespace Prefix: | ihg_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Longevity for future pensioners, males. + References No definition available. + Details
Name: | ihg_LongevityForFuturePensionersMales
Namespace Prefix: | ihg_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=ifrs-full_PensionDefinedBenefitPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_GeographicalAreasAxis=country_GB
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_GeographicalAreasAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |