CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Retained Earnings / Accumulated Deficit [Member]	Other Comprehensive Income / Loss [Member]	Total
Beginning balance, shares at Dec. 31, 2012	19,839,000
Beginning balance, value at Dec. 31, 2012	$ 65,678	$ 1,270	$ (5,637)	$ 61,311
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			3,864
Reclassification of warrants from debt	$ 583			583
Net income		21,005		21,005
Ending balance, shares at Dec. 31, 2013	24,016
Ending balance, value at Dec. 31, 2013	$ 73,422	22,275	(1,095)	94,602
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			3,835
Reclassification of warrants from debt	$ 583			0
Net income		29,516		29,516
Ending balance, shares at Dec. 31, 2014	25,541,000
Ending balance, value at Dec. 31, 2014	$ 80,513	51,791	(5,051)	127,253
Common stock issued upon exercise of options and warrants, shares	1,140,000
Common stock issued upon exercise of options and warrants, value	$ 1,726			1,726
Purchase of common stock, shares	(1,064)
Purchase of common stock, value	$ (5,926)			(5,926)
Pension benefit obligation			(1,599)	(1,599)
Stock-based compensation	$ 5,024			5,024
Reclassification of warrants from debt				0
Net income		34,681		34,681
Ending balance, shares at Dec. 31, 2015	25,617,000
Ending balance, value at Dec. 31, 2015	$ 81,337	$ 86,472	$ (6,650)	$ 161,159