(15) Segment Information Level 4 (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Oct. 02, 2011	Sep. 26, 2010	Oct. 02, 2011	Sep. 26, 2010
Segment Reporting Information [Line Items]
Consolidated net sales	$ 1,789.6	$ 1,508.1	$ 3,464.9	$ 2,954.9
Segment operating income (loss)	436.9	362.6	856.4	714.5
Interest expense	3.2	3.4	6.1	6.8
Interest income	(1.9)	(1.0)	(3.8)	(1.6)
Income before income tax expense and equity in earnings of unconsolidated affiliates	435.6	360.2	854.1	709.3
Investment Cast Products [Member]
Segment Reporting Information [Line Items]
Net sales	573.3	512.3	1,142.1	999.0
Segment operating income (loss)	189.9	162.5	377.0	317.6
Forged Products [Member]
Segment Reporting Information [Line Items]
Net sales	801.4	668.7	1,559.9	1,299.9
Segment operating income (loss)	164.1	130.2	320.6	250.3
Fastener Products [Member]
Segment Reporting Information [Line Items]
Net sales	414.9	327.1	762.9	656.0
Segment operating income (loss)	113.7	97.0	220.5	201.2
Corporate Expenses [Member]
Segment Reporting Information [Line Items]
Segment operating income (loss)	$ (30.8)	$ (27.1)	$ (61.7)	$ (54.6)

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Amount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. All considered to be "operating revenue" for purposes of the taxonomy.

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