Statement of Accounting Policy The balances in the Company's accumulated other comprehensive income (Details) (USD $)			3 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 Foreign Currency	Mar. 31, 2012 Foreign Currency	Jun. 30, 2011 Foreign Currency	Mar. 31, 2011 Foreign Currency	Jun. 30, 2012 Defined Benefit Pension Plans [Member]	Mar. 31, 2012 Defined Benefit Pension Plans [Member]	Jun. 30, 2011 Defined Benefit Pension Plans [Member]	Mar. 31, 2011 Defined Benefit Pension Plans [Member]	Jun. 30, 2012 Accumulative Other Comprehensive Income	Mar. 31, 2012 Accumulative Other Comprehensive Income	Jun. 30, 2011 Accumulative Other Comprehensive Income	Mar. 31, 2011 Accumulative Other Comprehensive Income	Jun. 30, 2012 Fair Value, Inputs, Level 2 [Member] Senior Notes [Member]
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Senior Notes	$ 35,000,000
Fair value of debt instrument															36,800,000
Accumlated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	8,699,000	7,294,000	11,379,000	9,994,000	14,044,000	12,234,000	(2,068,000)	(2,700,000)	(2,070,000)	(2,070,000)	9,311,000	7,294,000	11,974,000	10,164,000
Current-period other comprehensive income			(612,000)		824,000	1,810,000	0		0	0	(612,000)		824,000	1,810,000
Current-period other comprehensive income				1,385,000				0				1,385,000
Tax effect of pension liability from prior periods				0				632,000				632,000
Ending balance	$ 8,699,000	$ 7,294,000	$ 10,767,000	$ 11,379,000	$ 14,868,000	$ 14,044,000	$ (2,068,000)	$ (2,068,000)	$ (2,070,000)	$ (2,070,000)	$ 8,699,000	$ 9,311,000	$ 12,798,000	$ 11,974,000