Organization and Summary of Significant Accounting Policies (Details) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2009	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Organization and Summary of Significant Accounting Policies [Abstract]
Number of sales centers in North America and Europe		298
Number of distribution networks		3
Shipping and handling costs associated with outbound freight		$ 33,588,000	$ 29,924,000	$ 28,482,000
Advertising expense		5,484,000	5,534,000	4,990,000
Losses (gains) of foreign currency transactions		(592,000)	1,498,000	1,846,000
Number of interest rate swaps currently in place		3
Threshold past due account balances for reserve analysis		20,000
Threshold past due days for reserve analysis		60
Depreciation expense		9,746,000	8,980,000	9,091,000
Required terms of payment from customers, maximum (in days)		30
Cash paid during the year for [Abstract]
Interest		7,104,000	7,690,000	10,968,000
Income taxes, net of refunds		39,771,000	25,965,000	60,234,000
Payment of deferred 2008 estimated federal income taxes				30,000,000
Schedule of Equity Method Investments [Line Items]
Equity method investment loss				(28,700,000)
Equity method investment impairment	(26,500,000)
Building [Member]
Property, Plant and Equipment [Line Items]
Useful life, average (in years)		40
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)		5
Useful life, maximum (in years)		10
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)		1
Useful life, maximum (in years)		10
Autos and Trucks [Member]
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)		3
Useful life, maximum (in years)		5
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)		3
Useful life, maximum (in years)		10
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)		3
Useful life, maximum (in years)		7
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	13,688,000	7,102,000	11,426,000	13,688,000
Bad debt expense		2,958,000	779,000	4,643,000
Write-offs, net of recoveries		(4,160,000)	(5,103,000)	(6,405,000)
Reclassified balance		0	0	(500,000)
Balance at end of year			7,102,000	11,426,000
Balance at beginning of year			7,102,000	11,426,000
Balance at end of year			7,102,000	11,426,000
Inventory Valuation Reserve [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	8,448,000	7,084,000	7,805,000	8,448,000
Bad debt expense		3,590,000	875,000	1,967,000
Balance at end of year			7,084,000	7,805,000
Balance at beginning of year			7,084,000	7,805,000
Acquisition of businesses, net		0		(619,000)
Deduction for inventory write-offs		(3,601,000)	(1,596,000)	(1,991,000)
Balance at end of year			$ 7,084,000	$ 7,805,000
Northpark Corporate Center, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage (in hundredths)		50.00%
Latham Acquisition Corporation [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage (in hundredths)		0.00%	0.00%	38.00%