Description of business and summary of significant accounting policies - Principles of Consolidation and Non-Controlling Interest (Details)	Jun. 30, 2026	Dec. 31, 2025
Smith Douglas Holdings LLC
Noncontrolling Interest [Abstract]
Percentage of non-controlling interest	82.30%	82.50%

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant