Derivative Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Summary of Fair Value of Derivatives by Balance Sheet Line Item

The following tables display the fair value of derivatives by balance sheet line item at March 31, 2018 and December 31, 2017:

	March 31, 2018
	Other Current Assets		Other Non-current Assets		Accrued Liabilities		Other Non-current Liabilities
(Dollars in thousands)
Foreign exchange forward contracts and collars designated as hedging instruments	$	4,410		7,255		766		2,871
Foreign exchange forward contracts not designated as hedging instruments		766		—		66		—
Aluminum forward contracts designated as hedges		2		—		1,310		—
Cross currency swap not designated as hedging instrument		—		—		2,190		734
Embedded derivative liability		—		—		—		3,787
Total derivative financial instruments	$	5,178		7,255		4,332		7,392
	December 31, 2017
	Other Current Assets		Other Non-current Assets		Accrued Liabilities		Other Non-current Liabilities
(Dollars in thousands)
Foreign exchange forward contracts and collars designated as hedging instruments	$	3,065		723		4,922		8,405
Foreign exchange forward contracts not designated as hedging instruments		721		—		206		—
Aluminum forward contracts not designated as hedges		1,833		—		—		—
Cross currency swap not designated as hedging instrument		—		—		1,467		1,106
Embedded derivative liability		—		—		—		4,685
Total derivative financial instruments	$	5,619		723		6,595		14,196

Summary of Notional Amount and Estimated Fair Value of Derivative Financial Instruments

The following table summarizes the notional amount and estimated fair value of our derivative financial instruments:

	March 31, 2018					December 31, 2017
	Notional U.S. Dollar Amount		Fair Value			Notional U.S. Dollar Amount		Fair Value
(Dollars in thousands)
Foreign currency forward contracts and collars designated as hedging instruments	$	514,333	$	8,028		$	397,744	$	(9,539	)
Foreign exchange forward contracts not designated as hedging instruments		29,004		700			23,305		515
Aluminum forward contracts designated as hedges		24,038		(1,308	)		—		—
Aluminum forward contracts not designated as hedges		—		—			15,564		1,833
Cross currency swap not designated as hedging instrument		30,378		(2,924	)		36,454		(2,573	)
Total derivative financial instruments	$	597,753	$	4,496		$	473,067	$	(9,764	)

Schedule of Impact of Derivative Instruments Designated as Cash Flow Hedges

The following table provides the impact of derivative instruments designated as cash flow hedges on our statement of operations:

Three Months Ended March 31, 2018	Amount of Gain or (Loss) Recognized in AOCI on Derivatives (Effective Portion), Net of Tax		Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)			Amount of Pre-tax Gain or (Loss) Recognized in Income  on Derivatives (Amount Excluded from Effectiveness Testing)
(Dollars in thousands)
Derivative contracts	$	13,910	$	585		$	(744	)
Total	$	13,910	$	585		$	(744	)
Three Months ended March 26, 2017	Amount of Gain or (Loss) Recognized in AOCI on Derivatives (Effective Portion), Net of Tax		Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)			Amount of Pre-tax Gain or (Loss) Recognized in Income  on Derivatives (Amount Excluded from Effectiveness Testing)
(Dollars in thousands)
Derivative contracts	$	17,059	$	(2,491	)	$	168
Total	$	17,059	$	(2,491	)	$	168