Derivative Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2019

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 June 30, 2019 and December 31, 2018:

	June 30, 2019
	Other Current Assets		Other Non-current Assets		Accrued Liabilities		Other Non-current Liabilities
(Dollars in thousands)
Foreign exchange forward contracts designated as    hedging instruments	$	5,665	$	6,645	$	56	$	779
Foreign exchange forward contracts not designated    as hedging instruments		5		—		251		—
Aluminum forward contracts designated as hedging    instruments		—		—		681		—
Natural gas forward contracts designated as hedging    instruments		—		34		557		242
Interest rate swaps designated as hedging    instruments		—		—		1,855		4,552
Embedded derivative liability		—		—		—		2,415
Total derivative financial instruments	$	5,670	$	6,679	$	3,400	$	7,988

	December 31, 2018
	Other Current Assets		Other Non-current Assets		Accrued Liabilities		Other Non-current Liabilities
(Dollars in thousands)
Foreign exchange forward contracts designated as    hedging instruments	$	2,599	$	1,011	$	659	$	6,202
Foreign exchange forward contracts not designated    as hedging instruments		333		—		207		—
Aluminum forward contracts designated as hedging    instruments		—		—		927		—
Cross currency swap not designated as a hedging    instrument		—		—		227		—
Natural gas forward contracts designated as hedging    instruments		275		—		355		—
Interest rate swaps designated as hedging    instruments		—		—		131		128
Embedded derivative liability		—		—		—		3,134
Total derivative financial instruments	$	3,207	$	1,011	$	2,506	$	9,464

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:

	June 30, 2019					December 31, 2018
	Notional U.S. Dollar Amount		Fair Value			Notional U.S. Dollar Amount		Fair Value
(Dollars in thousands)
Foreign exchange forward contracts designated as    hedging instruments	$	468,440	$	11,475		$	467,253	$	(3,251	)
Foreign exchange forward contracts not designated    as hedging instruments		73,116		(246	)		45,905		126
Aluminum forward contracts designated as hedging    instruments		11,964		(681	)		10,810		(927	)
Cross currency swap not designated as a hedging    instrument		—		—			12,151		(227	)
Natural gas forward contracts designated as hedging    instruments		6,313		(765	)		2,165		(80	)
Interest rate swaps designated as hedging    instruments		290,000		(6,407	)		90,000		(259	)
Total derivative financial instruments	$	849,833	$	3,376		$	628,284	$	(4,618	)

Summary of Gain or Loss Recognized in AOCI

The following tables summarize the gain or loss recognized in AOCI as of June 30, 2019 and 2018, the amounts reclassified from AOCI into earnings and the amounts recognized directly into earnings for the three and six months ended June 30, 2019 and 2018:

Three months ended June 30, 2019	Amount of Gain or (Loss) Recognized in AOCI on Derivatives,          net of tax		Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income		Amount of Pre-tax Gain or (Loss) Recognized in Income on Derivatives
(Dollars in thousands)
Derivative contracts	$	1,856	$	878	$	56
Total	$	1,856	$	878	$	56
Six months ended June 30, 2019	Amount of Gain or (Loss) Recognized in AOCI on Derivatives,          net of tax		Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income		Amount of Pre-tax Gain or (Loss) Recognized in Income on Derivatives
(Dollars in thousands)
Derivative contracts	$	6,782	$	1,714	$	1,740
Total	$	6,782	$	1,714	$	1,740

Three months ended June 30, 2018	Amount of Gain or (Loss) Recognized in AOCI on Derivatives,           net of tax			Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income			Amount of Pre-tax Gain or (Loss) Recognized in Income on Derivatives
(Dollars in thousands)
Derivative contracts	$	(17,989	)	$	(539	)	$	435
Total	$	(17,989	)	$	(539	)	$	435
Six months ended June 30, 2018	Amount of Gain or (Loss) Recognized in AOCI on Derivatives,           net of tax			Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income			Amount of Pre-tax Gain or (Loss) Recognized in Income on Derivatives
(Dollars in thousands)
Derivative contracts	$	(4,079	)	$	46		$	(309	)
Total	$	(4,079	)	$	46		$	(309	)