Accumulated Other Comprehensive Loss - Schedule of Components of Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Equity [Abstract]
Tax effect of net unrealized gains (losses) on financial instruments	$ 3.2	$ (1.8)
Tax effect of pension obligation adjustment	$ 12.1	$ 11.1

Tax effect of the total net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s).

No definition available.

Name:	hxl_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansTaxEffect
Namespace Prefix:	hxl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant