Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Voting Common Stock [Member] Common Stock [Member]	Voting Common Stock [Member]	Nonvoting Common Stock [Member] Common Stock [Member]	Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Shareholders' Equity [Member]	Total
Treasury stock		$ (9,592)
Treasury stock, shares		154,494
Balance at Dec. 31, 2014	$ 216		$ 95	$ 1,017,520	$ (803,378)	$ (29,221)	$ 175,640
Balance, shares at Dec. 31, 2014	21,569,000		9,506,000
Net income (loss)					(70,282)
Other comprehensive income (loss)						523
Comprehensive income (loss)							(69,759)
Exercise of restricted stock units, shares	13,000
Adjustment to tax benefit associated with stock-based compensation				2,609			2,609
Balance at Dec. 31, 2015	$ 216		$ 95	1,020,129	(873,660)	(28,698)	108,490
Balance, shares at Dec. 31, 2015	21,582,000		9,506,000
Treasury stock		$ (9,592)
Treasury stock, shares		154,494
Net income (loss)					23,774			$ 23,774
Other comprehensive income (loss)						9,159		9,159
Comprehensive income (loss)							32,933	$ 32,933
Balance at Mar. 31, 2016	$ 216		$ 95	$ 1,020,129	$ (849,886)	$ (19,539)	$ 141,423
Balance, shares at Mar. 31, 2016	21,582,000		9,506,000
Treasury stock		$ (9,592)
Treasury stock, shares		154,494