Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Voting Common Stock [Member] Common Stock [Member]	Nonvoting Common Stock [Member] Common Stock [Member]	Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Shareholders' Equity [Member]	Total
Balance at Dec. 31, 2013	$ 216	$ 95	$ 1,015,656	$ (9,592)	$ (777,549)	$ (20,916)	$ 207,910
Balance, shares at Dec. 31, 2013	21,569	9,506		154
Net income (loss)					(25,829)
Other comprehensive income (loss)						(8,305)
Comprehensive income (loss)							(34,134)
Adjustment to tax benefit associated with stock-based compensation			1,864				1,864
Balance at Dec. 31, 2014	$ 216	$ 95	1,017,520	$ (9,592)	(803,378)	(29,221)	175,640
Balance, shares at Dec. 31, 2014	21,569	9,506		154
Net income (loss)					(68,397)			$ (68,397)
Other comprehensive income (loss)						664		664
Comprehensive income (loss)							(67,733)	$ (67,733)
Settlement of restricted stock units, shares	13
Adjustment to tax benefit associated with stock-based compensation			2,570				2,570
Balance at Sep. 30, 2015	$ 216	$ 95	$ 1,020,090	$ (9,592)	$ (871,775)	$ (28,557)	$ 110,477
Balance, shares at Sep. 30, 2015	21,582	9,506		154