Commitments under Operating and Finance Leases - Additional Information (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of maturity analysis of operating lease payments [abstract]
Operating lease commitments for discontinued operations	€ 0	€ 252	€ 237

Operating lease commitments for discontinued operations.

No definition available.

Name:	crh_OperatingLeaseCommitmentsForDiscontinuedOperations
Namespace Prefix:	crh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration