Derivatives (Tables)

3 Months Ended

Mar. 31, 2016

Derivative Instruments, Gain (Loss) [Line Items]

Schedule of Derivative Assets and Liabilities at Fair Value

The following table provides the fair values of our derivative financial instruments for the periods presented:

	Asset Derivatives:
(dollars in thousands)	March 31, 2016			December 31, 2015
Derivatives not designated as hedging instruments under FASB ASC 815:	Balance Sheet Location	Fair Value		Balance Sheet Location	Fair Value
Currency contracts	Prepaid and other current assets	$	—	Prepaid and other current assets	$	245
Total undesignated		—			245
Total		$	—		$	245
	Liability Derivatives:
(dollars in thousands)	March 31, 2016			December 31, 2015
Derivatives designated as hedging instruments under FASB ASC 815:	Balance Sheet Location	Fair Value		Balance Sheet Location	Fair Value
Natural gas contracts	Derivative liability - current	$	1,129	Derivative liability - current	$	1,069
Natural gas contracts	Other long-term liabilities	50		Other long-term liabilities	34
Interest rate contract	Derivative liability - current	2,322		Derivative liability - current	2,132
Interest rate contract	Other long-term liabilities	2,884		Other long-term liabilities	246
Total designated		6,385			3,481
Derivatives not designated as hedging instruments under FASB ASC 815:
Currency contracts	Derivative liability - current	173		Derivative liability - current	—
Natural gas contracts	Derivative liability - current	722		Derivative liability - current	1,064
Natural gas contracts	Other long-term liabilities	7		Other long-term liabilities	35
Total undesignated		902			1,099
Total		$	7,287		$	4,580

Summary of the Effective Portion of Derivative Gain (Loss) Recognized in Other Comprehensive Income (Loss)

The following table provides a summary of the effective portion of derivative gain (loss) recognized in other comprehensive income (loss) from our interest rate swap:

	Three months ended March 31,
(dollars in thousands)	2016			2015
Derivatives in Cash Flow Hedging relationships:
Interest rate swap	$	(3,219	)	$	—
Total	$	(3,219	)	$	—

The following table provides a summary of the effective portion of derivative gain (loss) recognized in other comprehensive income (loss) from our natural gas contracts:

	Three months ended March 31,
(dollars in thousands)	2016			2015
Derivatives in Cash Flow Hedging relationships:
Natural gas contracts	$	(616	)	$	(829	)
Total	$	(616	)	$	(829	)

Reclassification out of Accumulated Other Comprehensive Income

The following table provides a summary of the effective portion of derivative gain (loss) reclassified from accumulated other comprehensive loss to the Condensed Consolidated Statements of Operations from our natural gas contracts:

		Three months ended March 31,
(dollars in thousands)		2016			2015
Derivative:	Location:
Natural gas contracts	Cost of sales	$	(540	)	$	(536	)
Total impact on net income (loss)		$	(540	)	$	(536	)

The following table provides a summary of the effective portion of derivative gain (loss) reclassified from accumulated other comprehensive income (loss) to the Condensed Consolidated Statements of Operations from our interest rate swap:

		Three months ended March 31,
(dollars in thousands)		2016			2015
Derivative:	Location:
Interest rate swap	Interest expense	$	(391	)	$	—
Total impact on net income (loss)		$	(391	)	$	—

Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location

Gains (losses) on currency derivatives that were not designated as hedging instruments are recorded in other income (expense) as follows:

		Three months ended March 31,
(dollars in thousands)		2016			2015
Derivative:	Location:
Currency contracts	Other income (expense)	$	(418	)	$	74
Total		$	(418	)	$	74

Natural Gas Contracts

Derivative Instruments, Gain (Loss) [Line Items]

Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance

The following table provides a summary of the gain (loss) recognized in other income (expense) in the Condensed Consolidated Statements of Operations from our natural gas contracts:

	Three months ended March 31,
(dollars in thousands)	2016		2015
De-designated contracts	$	—	$	(104	)
Contracts where hedge accounting was not elected	370		(295		)
Total	$	370	$	(399	)