Schedule II - Consolidated Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Allowance For Doubtful Accounts And Sales Allowances [Member]
Valuation and Qualifying Accounts Roll Forward]
Balance at beginning of year	$ 10,349	$ 11,187	$ 12,658
Additions charged to costs and expenses	2,816	1,558	2,762
Deductions	(2,842)	(2,900)	(4,874)
Other	313	504	641
Balance at end of year	10,636	10,349	11,187
Reserve for inventory obsolescence [Member]
Valuation and Qualifying Accounts Roll Forward]
Balance at beginning of year	32,516	29,037	30,108
Additions charged to costs and expenses	11,407	12,905	8,789
Deductions	(8,848)	(9,125)	(10,508)
Other	149	(301)	648
Balance at end of year	$ 35,224	$ 32,516	$ 29,037