Supplemental Guarantor Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Supplemental guarantor information statements of operation
Net sales	$ 2,680	$ 2,401
Cost of goods sold (exclusive of depreciation and amortization)	2,329	2,098
Selling, general and administrative expenses	108	120
Depreciation and amortization	89	77
Research and development expenses	12	10
Interest expense and amortization of debt issuance costs	81	76
Gain on assets held for sale	(11)	0
Restructuring and impairment, net	6	9
Equity in net (income) loss of non-consolidated affiliates	2	4
Equity in net (income) loss in consolidated subsidiaries	0	0
Other (income) expense, net	5	(10)
Total expenses	2,621	2,384
Income (loss) before income taxes	59	17
Income tax (benefit) provision	24	3
Net income	35	14
Net Income (Loss) Attributable to Noncontrolling Interest	0	0
Net income (loss) attributable to our common shareholder	35	14
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	67	(29)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	1	(1)
Comprehensive income (loss) attributable to our common shareholder	66	(28)
Parent [Member]
Supplemental guarantor information statements of operation
Net sales	174	178
Cost of goods sold (exclusive of depreciation and amortization)	172	189
Selling, general and administrative expenses	(4)	44
Depreciation and amortization	4	4
Research and development expenses	0	1
Interest expense and amortization of debt issuance costs	80	79
Gain on assets held for sale	(5)
Restructuring and impairment, net	0	0
Equity in net (income) loss of non-consolidated affiliates	0	0
Equity in net (income) loss in consolidated subsidiaries	(90)	(155)
Other (income) expense, net	(20)	2
Total expenses	137	164
Income (loss) before income taxes	37	14
Income tax (benefit) provision	2	0
Net income	35	14
Net Income (Loss) Attributable to Noncontrolling Interest	0	0
Net income (loss) attributable to our common shareholder	35	14
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	66	(28)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0	0
Comprehensive income (loss) attributable to our common shareholder	66	(28)
Guarantors [Member]
Supplemental guarantor information statements of operation
Net sales	2,235	1,962
Cost of goods sold (exclusive of depreciation and amortization)	1,950	1,717
Selling, general and administrative expenses	91	63
Depreciation and amortization	64	58
Research and development expenses	12	9
Interest expense and amortization of debt issuance costs	14	7
Gain on assets held for sale	(6)
Restructuring and impairment, net	5	8
Equity in net (income) loss of non-consolidated affiliates	2	4
Equity in net (income) loss in consolidated subsidiaries	(9)	(26)
Other (income) expense, net	4	(29)
Total expenses	2,127	1,811
Income (loss) before income taxes	108	151
Income tax (benefit) provision	18	(2)
Net income	90	153
Net Income (Loss) Attributable to Noncontrolling Interest	0	0
Net income (loss) attributable to our common shareholder	90	153
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	74	172
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0	0
Comprehensive income (loss) attributable to our common shareholder	74	172
Non-Guarantor [Member]
Supplemental guarantor information statements of operation
Net sales	685	626
Cost of goods sold (exclusive of depreciation and amortization)	621	557
Selling, general and administrative expenses	21	13
Depreciation and amortization	21	15
Research and development expenses	0	0
Interest expense and amortization of debt issuance costs	3	(1)
Gain on assets held for sale	0
Restructuring and impairment, net	1	1
Equity in net (income) loss of non-consolidated affiliates	0	0
Equity in net (income) loss in consolidated subsidiaries	0	0
Other (income) expense, net	5	8
Total expenses	672	593
Income (loss) before income taxes	13	33
Income tax (benefit) provision	4	5
Net income	9	28
Net Income (Loss) Attributable to Noncontrolling Interest	0	0
Net income (loss) attributable to our common shareholder	9	28
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	44	6
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	1	(1)
Comprehensive income (loss) attributable to our common shareholder	43	7
Eliminations [Member]
Supplemental guarantor information statements of operation
Net sales	(414)	(365)
Cost of goods sold (exclusive of depreciation and amortization)	(414)	(365)
Selling, general and administrative expenses	0	0
Depreciation and amortization	0	0
Research and development expenses	0	0
Interest expense and amortization of debt issuance costs	(16)	(9)
Gain on assets held for sale	0
Restructuring and impairment, net	0	0
Equity in net (income) loss of non-consolidated affiliates	0	0
Equity in net (income) loss in consolidated subsidiaries	99	181
Other (income) expense, net	16	9
Total expenses	(315)	(184)
Income (loss) before income taxes	(99)	(181)
Income tax (benefit) provision	0	0
Net income	(99)	(181)
Net Income (Loss) Attributable to Noncontrolling Interest	0	0
Net income (loss) attributable to our common shareholder	(99)	(181)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(117)	(179)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0	0
Comprehensive income (loss) attributable to our common shareholder	$ (117)	$ (179)