Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Statement of Comprehensive Income [Abstract]
Net income	$ 37.8	$ 23.6
Currency translation adjustment:
Unrealized gains (losses) arising during the period, net of tax expense (benefit)	(0.4)	0.0
Other comprehensive income (loss)	(0.4)	0.0
Comprehensive income	$ 37.4	$ 23.6

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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+ Details

Arcosa, Inc. 10-Q