Acres Of Land

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Beneficial Owner Of Companys Common Stock

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Business Acquisition Cost Of Acquired Entity Purchase Price Net

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Estimated Asset Retirement Period

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Maximum Percentage Of Likelihood Of Tax Benefit Being Realized

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Number Of Employees Covered By Collective Bargaining Agreements

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Percentage Of Accounts Receivable

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Percentage Of Employees Collective Bargaining Agreement

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Percentage Of Likelihood That Fair Value Of Reporting Unit Is Less Than Its Carrying Amount

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Percentage Of Net Sales By Segment

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Repurchase Of Debentures

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount paid or received to resolve the preacquisition contingency.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended	12 Months Ended
	Nov. 30, 2012 Employees	Nov. 30, 2011	Nov. 30, 2010	May 31, 2013 acre Employees	Nov. 30, 2012 acre Employees	Nov. 30, 2011	Nov. 30, 2010	Jul. 31, 2012
Segment Reporting Information [Line Items]
Acres of land owned by the company				11,900	11,900
Acquisition, purchase price								$ 550
Termination fee	20.0				20.0
Acquisition expenses of Rocketdyne Business	11.6				11.6
Intercompany adjustment in state tax provisions					0.2	(0.8)	2.8
Income tax out of period adjustments	0.4	1.0				0.8
Percentage of tax benefit to be realized					50.00%
Estimated retirement period of assets expected to be retired in 15 years					30 years
Impairment charge of long-lived asset			1.6
Foreign currency transaction gains and (losses)					0.4	(0.3)	1.7
Manager of company owns, percentage	99.00%	99.00%			99.00%	99.00%
Beneficial owner of company's common stock, percentage					5.00%	5.00%
Percentage of net sales				10.00%	10.00%
Percentage of accounts receivable	10.00%				10.00%
No. of employees under collective bargaining agreements	3,391				3,391
Percentage of employees under collective bargaining agreements					13.00%
Percentage of likelihood that fair value is less than its carrying amount					50.00%
U.S. Government and agencies [Member]
Segment Reporting Information [Line Items]
Percentage of sales to U.S government and its agencies					25.00%	24.00%	26.00%
Company-sponsored [Member]
Segment Reporting Information [Line Items]
Research and development expenses					30.3	27.4	17.4
Customer-sponsored [Member]
Segment Reporting Information [Line Items]
Research and development expenses					271.8	276.0	283.7
Minimum [Member]
Segment Reporting Information [Line Items]
Amortization periods for identifiable intangible					20 years
Maximum [Member]
Segment Reporting Information [Line Items]
Amortization periods for identifiable intangible					27 years
9.5% Senior Subordinated Notes [Member]
Segment Reporting Information [Line Items]
Percentage of debt instrument	9.50%				9.50%
Convertible subordinated debentures bearing interest at 4.0625% maturing in December 2034 [Member]
Segment Reporting Information [Line Items]
Percentage of debt instrument	4.0625%			4.0625%	4.0625%
2.25% Convertible Subordinated Debentures [Member]
Segment Reporting Information [Line Items]
Percentage of debt instrument		2.25%				2.25%
Repurchase of 21/4% Convertible Subordinated Debentures						$ 15.5