Redeemable noncontrolling interests - Narrative (Details)	Mar. 31, 2026 subsidiary
Noncontrolling Interest [Abstract]
Number of subsidiaries with redeemable noncontrolling interests	2

Number of Subsidiaries with Redeemable Noncontrolling Interests

No definition available.

Name:	crh_NumberOfSubsidiariesWithRedeemableNoncontrollingInterests
Namespace Prefix:	crh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant