Guarantor Financial Information (Condensed Consolidated Statements of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Net sales	$ 425,786	$ 452,732	$ 1,294,801	$ 1,276,514
Costs and expenses:
Cost of sales and operating expenses	310,089	327,909	942,697	918,516
Selling, general and administrative expenses	42,588	38,523	124,843	112,786
Acquisition Costs	8,326	0	9,157	0
Depreciation and amortization	23,131	20,524	67,074	62,958
Total costs and expenses	384,134	386,956	1,143,771	1,094,260
Operating income	41,652	65,776	151,030	182,254
Interest expense	(5,313)	(5,868)	(16,607)	(18,546)
Other income/(expense), net	(3,268)	232	(2,619)	(106)
Equity in net income/(loss) of unconsolidated subsidiary	11,953	(833)	8,796	(1,725)
Earnings in investments in subsidiaries	0	0	0	0
Income before income taxes	45,024	59,307	140,600	161,877
Income taxes	17,373	22,135	54,126	59,909
Net income	27,651	37,172	86,474	101,968
Issuer [Member]
Net sales	182,331	165,256	503,595	502,814
Costs and expenses:
Cost of sales and operating expenses	140,213	125,806	388,463	389,808
Selling, general and administrative expenses	23,142	20,396	66,984	60,108
Acquisition Costs	8,326		9,157
Depreciation and amortization	6,035	5,502	17,990	17,614
Total costs and expenses	177,716	151,704	482,594	467,530
Operating income	4,615	13,552	21,001	35,284
Interest expense	(5,309)	(5,867)	(16,596)	(18,544)
Other income/(expense), net	(3,023)	(841)	(2,697)	(2,071)
Equity in net income/(loss) of unconsolidated subsidiary	0	0	0	0
Earnings in investments in subsidiaries	29,939	32,877	85,424	92,728
Income before income taxes	26,222	39,721	87,132	107,397
Income taxes	(1,429)	2,549	658	5,429
Net income	27,651	37,172	86,474	101,968
Guarantors [Member]
Net sales	309,529	330,013	938,629	903,712
Costs and expenses:
Cost of sales and operating expenses	235,902	244,924	701,804	659,207
Selling, general and administrative expenses	19,438	18,093	57,798	52,571
Acquisition Costs	0		0
Depreciation and amortization	17,091	15,016	49,067	45,327
Total costs and expenses	272,431	278,033	808,669	757,105
Operating income	37,098	51,980	129,960	146,607
Interest expense	(4)	(1)	(11)	(2)
Other income/(expense), net	(239)	1,076	108	1,981
Equity in net income/(loss) of unconsolidated subsidiary	0	0	0	0
Earnings in investments in subsidiaries	0	0	0	0
Income before income taxes	36,855	53,055	130,057	148,586
Income taxes	14,227	19,806	50,067	54,990
Net income	22,628	33,249	79,990	93,596
Non-guarantors [Member]
Net sales	2,293	3,814	8,188	10,089
Costs and expenses:
Cost of sales and operating expenses	2,341	3,530	8,041	9,602
Selling, general and administrative expenses	8	34	61	107
Acquisition Costs	0		0
Depreciation and amortization	5	6	17	17
Total costs and expenses	2,354	3,570	8,119	9,726
Operating income	(61)	244	69	363
Interest expense	0	0	0	0
Other income/(expense), net	(6)	(3)	(30)	(16)
Equity in net income/(loss) of unconsolidated subsidiary	11,953	(833)	8,796	(1,725)
Earnings in investments in subsidiaries	0	0	0	0
Income before income taxes	11,886	(592)	8,835	(1,378)
Income taxes	4,575	(220)	3,401	(510)
Net income	7,311	(372)	5,434	(868)
Eliminations [Member]
Net sales	(68,367)	(46,351)	(155,611)	(140,101)
Costs and expenses:
Cost of sales and operating expenses	(68,367)	(46,351)	(155,611)	(140,101)
Selling, general and administrative expenses	0	0	0	0
Acquisition Costs	0		0
Depreciation and amortization	0	0	0	0
Total costs and expenses	(68,367)	(46,351)	(155,611)	(140,101)
Operating income	0	0	0	0
Interest expense	0	0	0	0
Other income/(expense), net	0	0	0	0
Equity in net income/(loss) of unconsolidated subsidiary	0	0	0	0
Earnings in investments in subsidiaries	(29,939)	(32,877)	(85,424)	(92,728)
Income before income taxes	(29,939)	(32,877)	(85,424)	(92,728)
Income taxes	0	0	0	0
Net income	$ (29,939)	$ (32,877)	$ (85,424)	$ (92,728)