Supplemental Guarantor Condensed Consolidating Financial Information - Condensed Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 26,090	$ 88,920	$ 10,540	$ 46,370
Trade receivables, net	185,040	135,610
Receivables, intercompany	0	0
Inventories	220,450	178,030
Deferred income taxes	18,510	18,510
Prepaid expenses and other current assets	10,150	10,620
Total current assets	460,240	431,690
Investments in subsidiaries	0	0
Property and equipment, net	180,100	159,210
Goodwill	269,260	215,360
Intangibles and other assets	235,690	180,280
Total assets	1,145,290	986,540
Current liabilities:
Current maturities, long-term debt	17,950	7,290
Accounts payable, trade	148,890	146,930
Accounts payable, intercompany	0	0
Accrued liabilities	79,480	70,140
Total current liabilities	246,320	224,360
Long-term debt	412,040	462,610
Deferred income taxes	66,340	64,780
Other long-term liabilities	78,780	61,000
Total liabilities	803,480	812,750
Redeemable noncontrolling interest	26,370	0
Total shareholders' equity	315,440	173,790
Total liabilities and shareholders' equity	1,145,290	986,540
Parent [Member]
Current assets:
Cash and cash equivalents	0	0	0	0
Trade receivables, net	0	0
Receivables, intercompany	0	0
Inventories	0	0
Deferred income taxes	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Investments in subsidiaries	513,420	412,840
Property and equipment, net	0	0
Goodwill	0	0
Intangibles and other assets	4,780	7,920
Total assets	518,200	420,760
Current liabilities:
Current maturities, long-term debt	0	0
Accounts payable, trade	0	0
Accounts payable, intercompany	0	0
Accrued liabilities	5,740	1,080
Total current liabilities	5,740	1,080
Long-term debt	197,020	245,890
Deferred income taxes	0	0
Other long-term liabilities	0	0
Total liabilities	202,760	246,970
Redeemable noncontrolling interest	0
Total shareholders' equity	315,440	173,790
Total liabilities and shareholders' equity	518,200	420,760
Guarantor [Member]
Current assets:
Cash and cash equivalents	5,860	33,820	120	15,070
Trade receivables, net	147,400	105,030
Receivables, intercompany	10,200	2,290
Inventories	163,700	147,010
Deferred income taxes	17,320	17,280
Prepaid expenses and other current assets	8,590	8,950
Total current assets	353,070	314,380
Investments in subsidiaries	170,050	169,360
Property and equipment, net	111,420	103,880
Goodwill	204,680	169,290
Intangibles and other assets	203,640	169,020
Total assets	1,042,860	925,930
Current liabilities:
Current maturities, long-term debt	2,330	7,290
Accounts payable, trade	110,260	115,150
Accounts payable, intercompany	0	0
Accrued liabilities	60,650	58,660
Total current liabilities	173,240	181,100
Long-term debt	215,020	216,720
Deferred income taxes	56,760	61,580
Other long-term liabilities	58,050	53,690
Total liabilities	503,070	513,090
Redeemable noncontrolling interest	26,370
Total shareholders' equity	513,420	412,840
Total liabilities and shareholders' equity	1,042,860	925,930
Non-Guarantor [Member]
Current assets:
Cash and cash equivalents	20,230	55,100	10,420	31,300
Trade receivables, net	37,640	30,580
Receivables, intercompany	0	0
Inventories	56,750	31,020
Deferred income taxes	1,190	1,230
Prepaid expenses and other current assets	1,560	1,670
Total current assets	117,370	119,600
Investments in subsidiaries	0	0
Property and equipment, net	68,680	55,330
Goodwill	64,580	46,070
Intangibles and other assets	28,610	6,350
Total assets	279,240	227,350
Current liabilities:
Current maturities, long-term debt	15,620	0
Accounts payable, trade	38,630	31,780
Accounts payable, intercompany	10,200	2,290
Accrued liabilities	13,090	10,400
Total current liabilities	77,540	44,470
Long-term debt	0	0
Deferred income taxes	10,920	6,210
Other long-term liabilities	20,730	7,310
Total liabilities	109,190	57,990
Redeemable noncontrolling interest	0
Total shareholders' equity	170,050	169,360
Total liabilities and shareholders' equity	279,240	227,350
Eliminations [Member]
Current assets:
Cash and cash equivalents	0	0	0	0
Trade receivables, net	0	0
Receivables, intercompany	(10,200)	(2,290)
Inventories	0	0
Deferred income taxes	0	0
Prepaid expenses and other current assets	0	0
Total current assets	(10,200)	(2,290)
Investments in subsidiaries	(683,470)	(582,200)
Property and equipment, net	0	0
Goodwill	0	0
Intangibles and other assets	(1,340)	(3,010)
Total assets	(695,010)	(587,500)
Current liabilities:
Current maturities, long-term debt	0	0
Accounts payable, trade	0	0
Accounts payable, intercompany	(10,200)	(2,290)
Accrued liabilities	0	0
Total current liabilities	(10,200)	(2,290)
Long-term debt	0	0
Deferred income taxes	(1,340)	(3,010)
Other long-term liabilities	0	0
Total liabilities	(11,540)	(5,300)
Redeemable noncontrolling interest	0
Total shareholders' equity	(683,470)	(582,200)
Total liabilities and shareholders' equity	$ (695,010)	$ (587,500)