SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for doubtful accounts
Movement in valuation and qualifying accounts
Balance at Beginning of Year	$ 4,203	$ 3,645	$ 5,094
Additions Charged to Expenses	1,443	1,726	1,476
Charge-Offs	133	1,170	2,917
Other	1	2	(8)
Balance at End of Year	5,514	4,203	3,645
Allowance for other non-trade receivables
Movement in valuation and qualifying accounts
Balance at Beginning of Year			118
Charge-Offs			118
Reserve for inventory valuation
Movement in valuation and qualifying accounts
Balance at Beginning of Year	7,743	8,297	8,437
Additions Charged to Expenses	1,309	1,515	2,210
Charge-Offs	2,146	2,057	1,911
Other	10	(12)	(439)
Balance at End of Year	6,916	7,743	8,297
Valuation allowance for deferred income tax assets
Movement in valuation and qualifying accounts
Balance at Beginning of Year	7,385	7,506	8,314
Additions Charged to Expenses	646	219	(106)
Other	(233)	(340)	(702)
Balance at End of Year	$ 7,798	$ 7,385	$ 7,506