SELECTED CONSOLIDATING FINANCIAL STATEMENTS OF PARENT, GUARANTORS AND NON-GUARANTORS (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Consolidating Financial Statements, Captions
Net sales	$ 890,565			$ 825,962	$ 2,716,434	$ 2,461,553
Operating costs and expenses:
Cost of sales	663,800			618,602	2,018,732	1,858,600
Selling, general and administrative	57,794			57,494	175,947	178,714
Depreciation and amortization	32,331			30,131	96,144	89,064
Acquisition and integration expenses	250			2,095	2,227	3,699
Defined Benefit Plan, Cost of Providing Special or Contractual Termination Benefits Recognized During Period	2,030	1,957	1,150		5,137
Total operating costs and expenses	756,205			708,322	2,298,187	2,130,077
Operating income (loss)	134,360			117,640	418,247	331,476
Intercompany interest and charges	0			0	0	0
Interest expense and other	16,768			14,543	50,668	58,676
Income (loss) from continuing operations, before income taxes	117,592			103,097	367,579	272,800
Income tax expense (benefit)	42,369			37,194	135,834	97,429
Income (loss) from continuing operations	75,223			65,903	231,745	175,371
Loss on discontinued operations, net	0			0	0	(765)
Net income	75,223			65,903	231,745	174,606
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	756			(4,079)	743	(10,113)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	75,979			61,824	232,488	164,493
Parent
Consolidating Financial Statements, Captions
Net sales	0			0	0	0
Operating costs and expenses:
Cost of sales	0			0	0	0
Selling, general and administrative	9,308			9,270	24,947	28,256
Depreciation and amortization	597			467	1,805	1,313
Acquisition and integration expenses	250			607	545	1,265
Defined Benefit Plan, Cost of Providing Special or Contractual Termination Benefits Recognized During Period	2,030				5,137
Total operating costs and expenses	12,185			10,344	32,434	30,834
Operating income (loss)	(12,185)			(10,344)	(32,434)	(30,834)
Intercompany interest and charges	(46,995)			(44,886)	(145,549)	(143,071)
Interest expense and other	14,756			16,118	45,399	59,684
Income (loss) from continuing operations, before income taxes	20,054			18,424	67,716	52,553
Income tax expense (benefit)	7,743			7,587	26,630	19,408
Income (loss) from continuing operations	12,311					33,145
Loss on discontinued operations, net						0
Net income				10,837	41,086	33,145
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0			0	0	232
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	12,311			10,837	41,086	33,377
Guarantors Subsidiaries
Consolidating Financial Statements, Captions
Net sales	868,740			802,380	2,646,159	2,389,284
Operating costs and expenses:
Cost of sales	648,436			600,874	1,978,224	1,802,655
Selling, general and administrative	44,060			43,866	136,312	137,567
Depreciation and amortization	30,604			28,347	91,019	83,791
Acquisition and integration expenses	0			1,488	1,682	2,434
Defined Benefit Plan, Cost of Providing Special or Contractual Termination Benefits Recognized During Period	0				0
Total operating costs and expenses	723,100			674,575	2,207,237	2,026,447
Operating income (loss)	145,640			127,805	438,922	362,837
Intercompany interest and charges	46,143			44,037	143,094	140,266
Interest expense and other	2,714			(791)	7,206	1,854
Income (loss) from continuing operations, before income taxes	96,783			84,559	288,622	220,717
Income tax expense (benefit)	34,641			29,653	108,626	78,191
Income (loss) from continuing operations	62,142					142,526
Loss on discontinued operations, net						(765)
Net income				54,906	179,996	141,761
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	119			(778)	437	(2,174)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	62,261			54,128	180,433	139,587
Non-Guarantor Subsidiaries
Consolidating Financial Statements, Captions
Net sales	22,773			24,675	73,948	77,719
Operating costs and expenses:
Cost of sales	16,312			18,821	44,181	61,395
Selling, general and administrative	4,426			4,358	14,688	12,891
Depreciation and amortization	1,130			1,317	3,320	3,960
Acquisition and integration expenses	0			0	0	0
Defined Benefit Plan, Cost of Providing Special or Contractual Termination Benefits Recognized During Period	0				0
Total operating costs and expenses	21,868			24,496	62,189	78,246
Operating income (loss)	905			179	11,759	(527)
Intercompany interest and charges	852			849	2,455	2,805
Interest expense and other	(702)			(784)	(1,937)	(2,862)
Income (loss) from continuing operations, before income taxes	755			114	11,241	(470)
Income tax expense (benefit)	(15)			(46)	578	(170)
Income (loss) from continuing operations	770					(300)
Loss on discontinued operations, net						0
Net income				160	10,663	(300)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	637			(3,301)	306	(8,171)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	1,407			(3,141)	10,969	(8,471)
Eliminations
Consolidating Financial Statements, Captions
Net sales	(948)			(1,093)	(3,673)	(5,450)
Operating costs and expenses:
Cost of sales	(948)			(1,093)	(3,673)	(5,450)
Selling, general and administrative	0			0	0	0
Depreciation and amortization	0			0		0
Acquisition and integration expenses	0			0	0	0
Defined Benefit Plan, Cost of Providing Special or Contractual Termination Benefits Recognized During Period	0				0
Total operating costs and expenses	(948)			(1,093)	(3,673)	(5,450)
Operating income (loss)	0			0	0	0
Intercompany interest and charges	0			0	0	0
Interest expense and other	0			0	0	0
Income (loss) from continuing operations, before income taxes	0			0	0	0
Income tax expense (benefit)	0			0	0	0
Income (loss) from continuing operations	0					0
Loss on discontinued operations, net						0
Net income				0	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0			0	0	0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 0			$ 0	$ 0	$ 0