CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data	Common Stock	Retained Earnings / Accumulated Deficit	Other Comprehensive Income / Loss	Total
Beginning balance, value at Dec. 31, 2011	$ 62,466	$ (68,138)	$ (8,535)	$ (14,207)us-gaap_StockholdersEquity
Beginning balance, shares at Dec. 31, 2011	19,527,000
Common stock issued upon exercise of options and warrants, shares	632,000
Common stock issued upon exercise of options and warrants, value	1,206			1,206
Purchase of common stock, shares	(320,000)
Purchase of common stock, value	(435)			(435)
Pension benefit obligation			2,898	2,898
Stock-based compensation	1,134			1,134us-gaap_ShareBasedCompensation
Reclassification of warrants from debt	1,307			1,307
Net income		69,408		69,408us-gaap_NetIncomeLoss
Ending balance, value at Dec. 31, 2012	65,678	1,270	(5,637)	61,311us-gaap_StockholdersEquity
Ending balance, shares at Dec. 31, 2012	19,839,000
Common stock issued upon exercise of options and warrants, shares	4,177,000
Common stock issued upon exercise of options and warrants, value	3,297			3,297
Pension benefit obligation			4,542	4,542
Stock-based compensation	3,864			3,864us-gaap_ShareBasedCompensation
Reclassification of warrants from debt	583			583
Net income		21,005		21,005us-gaap_NetIncomeLoss
Ending balance, value at Dec. 31, 2013	73,422	22,275	(1,095)	94,602us-gaap_StockholdersEquity
Ending balance, shares at Dec. 31, 2013	24,016,000
Common stock issued upon exercise of options and warrants, shares	1,525,000
Common stock issued upon exercise of options and warrants, value	3,256			3,256
Pension benefit obligation			(3,956)	(3,956)
Stock-based compensation	3,835			3,835us-gaap_ShareBasedCompensation
Reclassification of warrants from debt				0
Net income		29,516		29,516us-gaap_NetIncomeLoss
Ending balance, value at Dec. 31, 2014	$ 80,513	$ 51,791	$ (5,051)	$ 127,253us-gaap_StockholdersEquity
Ending balance, shares at Dec. 31, 2014	25,541,000

The amount of the liability for the conversion option reclassified to stockholders' equity when the embedded option no longer required separation from the host instrument.

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