Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at at Dec. 31, 2011	$ 270,147	$ 640	$ 520,613	$ (148,059)	$ (103,047)
Balance at (in shares) at Dec. 31, 2011		64,015,789
Stock-based compensation plans
Grant of restricted stock	0	3	(3)
Grant of restricted stock (in shares)		254,200
Withholdings of common shares, net of issuances	(756)	(1)	(755)
Withholdings of common shares, net of issuances (in shares)		(83,933)
Forfeited restricted stock	0	(1)	1
Forfeited restricted stock (in shares)		(56,000)
Amortization of stock awards and restricted stock	3,231		3,231
Total comprehensive income (loss)	26,634			40,874	(14,240)
Balance at at Dec. 31, 2012	299,256	641	523,087	(107,185)	(117,287)
Balance at (in shares) at Dec. 31, 2012		64,130,056
Stock-based compensation plans
Grant of restricted stock	0	3	(3)
Grant of restricted stock (in shares)		258,800
Withholdings of common shares, net of issuances	(1,048)	2	(1,050)
Issuance of common shares, net of withholdings (in shares)		238,049
Forfeited restricted stock	0	0	0
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	187		187
Forfeited restricted stock (in shares)		(8,600)
Amortization of stock awards and restricted stock	2,732		2,732
Total comprehensive income (loss)	67,841			(19,628)	87,469
Balance at at Dec. 31, 2013	368,968	646	524,953	(126,813)	(29,818)
Balance at (in shares) at Dec. 31, 2013	64,618,305	64,618,305
Stock-based compensation plans
Grant of restricted stock	0	2	(2)
Grant of restricted stock (in shares)		196,000
Withholdings of common shares, net of issuances	(938)	1	(939)
Withholdings of common shares, net of issuances (in shares)		49,545
Forfeited restricted stock	0	0	0
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	(267)		(267)
Forfeited restricted stock (in shares)		(8,900)
Amortization of stock awards and restricted stock	2,924		2,924
Total comprehensive income (loss)	(23,198)			29,860	(53,058)
Balance at at Dec. 31, 2014	$ 347,489	$ 649	$ 526,669	$ (96,953)	$ (82,876)
Balance at (in shares) at Dec. 31, 2014	64,854,950	64,854,950