Summary of Significant Accounting Policies (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Effects of the revisions on Consolidated Balance Sheet
Pension and retirement obligations - current portion	$ 626	$ 609
Total current liabilities	44,004	41,207
Pension and retirement obligations	20,261	17,896
Total long-term liabilities	270,251	266,583
Total liabilities	314,255	307,790
Accumulated deficit	(137,446)	(129,704)
Accumulated other comprehensive loss	(13,841)	(13,130)	(7,484)	(5,810)
Total deficit	(151,287)	(142,834)
Previously reported
Effects of the revisions on Consolidated Balance Sheet
Pension and retirement obligations - current portion		890
Total current liabilities		41,488
Pension and retirement obligations		17,953
Total long-term liabilities		266,640
Total liabilities		308,128
Accumulated deficit		(130,769)
Accumulated other comprehensive loss		(12,403)
Total deficit		(143,172)
Adjustments
Effects of the revisions on Consolidated Balance Sheet
Pension and retirement obligations - current portion		(281)
Total current liabilities		(281)
Pension and retirement obligations		(57)
Total long-term liabilities		(57)
Total liabilities		(338)
Accumulated deficit		1,065
Accumulated other comprehensive loss		(727)
Total deficit		$ 338