Fair Value Measurements - Additional Information (Details)	6 Months Ended
	Jun. 30, 2021 USD ($) item Liability	Dec. 31, 2020 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of counterparties, which experienced significant downgrades | item	0
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	$ 0
Liabilities	$ 0
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value measurement with unobservable inputs reconciliation, number of liabilities | Liability	1
Level 3 | OPM, Inc. Acquisition
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Acquisition of fair value liabilities, contingent consideration	$ 400,000
Level 2 | Fair Value Measured on Recurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	13,500,000	$ 18,400,000
Derivative liabilities	4,900,000	14,800,000
Level 2 | Fair Value Measured on Recurring Basis | Cross Currency And Interest Rate Swap
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	$ 1,700,000	$ 300,000
Derivative Asset, Measurement Input [Extensible List]	hxl:USDSecuredOvernightFinancingRateCurvesMember	hxl:USDSecuredOvernightFinancingRateCurvesMember
Derivative liabilities	$ 3,200,000	$ 11,100,000
Derivative Liability, Measurement Input [Extensible List]	hxl:USDSecuredOvernightFinancingRateCurvesMember	hxl:USDSecuredOvernightFinancingRateCurvesMember
Level 2 | Fair Value Measured on Recurring Basis | Foreign Currency Forward Exchange Contracts
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	$ 7,900,000	$ 16,000,000.0
Derivative Asset, Measurement Input [Extensible List]	us-gaap:MeasurementInputQuotedPriceMember	us-gaap:MeasurementInputQuotedPriceMember
Derivative liabilities	$ 1,700,000	$ 2,600,000
Derivative Liability, Measurement Input [Extensible List]	us-gaap:MeasurementInputQuotedPriceMember	us-gaap:MeasurementInputQuotedPriceMember
Level 2 | Fair Value Measured on Recurring Basis | Commodity Swap Agreements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	$ 3,900,000	$ 2,200,000
Derivative Asset, Measurement Input [Extensible List]	us-gaap:MeasurementInputQuotedPriceMember	us-gaap:MeasurementInputQuotedPriceMember
Derivative liabilities		$ 1,100,000
Derivative Liability, Measurement Input [Extensible List]		us-gaap:MeasurementInputQuotedPriceMember