Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Expected Long Term Return on Assets

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- Definition

Defined Benefit Plan, Contributions By Employer, Low Estimate

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- Definition

Defined Benefit Plans Period Over Which Investment Gains and Losses are Recognized for Market Related Value of Assets

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- Definition

Defined Benefit Plan, Voluntary Employer Contributions

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- Definition

Percentage of fair value to total pension plan asset

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- Definition

The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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- Definition

The aggregate amount in accumulated other comprehensive income expected to be recognized as a component of net periodic benefit cost over the fiscal year that follows the most recent annual statement of financial position presented, including the net gain (loss), net prior service cost or credit, and net transition asset or obligation.

+ References

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- Definition

The interest rate used to adjust for the time value of money for the plan.

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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- Definition

This represents the entire liability recognized in the balance sheet that is associated with other postretirement defined benefit plans (excluding pension plans).

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Postretirement Benefits - Additional Information (Detail) (USD $)	12 Months Ended					3 Months Ended	12 Months Ended				12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2011 Market Related Valuation of Assets	Sep. 30, 2011 Other actuarial losses	Sep. 30, 2011 Helix Plan	Sep. 30, 2011 Helix Plan	Sep. 30, 2010 Helix Plan	Sep. 30, 2011 Nexus Plan	Sep. 30, 2011 Taiwan Plan	Sep. 30, 2011 Worldwide Defined Contribution Plans	Sep. 30, 2010 Worldwide Defined Contribution Plans	Sep. 30, 2009 Worldwide Defined Contribution Plans	Sep. 30, 2011 Supplemental Key Executive Retirement Plan	Sep. 30, 2010 Supplemental Key Executive Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Investment gains or losses recognition period, years				5 years
Accumulated other comprehensive income, unrecognized net actuarial losses	$ 8,900,000	$ 8,400,000		$ 200,000	$ 9,200,000
Net actuarial loss in accumulated other comprehensive income that is expected to be recognized as a component of net periodic pension cost	600,000
Discount rate	3.76%	4.75%	5.50%			4.38%	4.38%	4.75%	2.30%
Expected return on plan assets	4.68%	6.50%
Fair value of plan assets	20,173,000	9,990,000	5,860,000			11,600,000	11,600,000		8,100,000	500,000
Percentage of fair value to total pension plan asset						58.00%	58.00%
Voluntary contribution to the Plan						200,000
Required minimum contributions	600,000						600,000
Expected contribution to the Plan to meet minimum funding targets	700,000
Employer contributions	778,000	4,204,000									2,900,000	2,600,000	2,700,000
Accrued benefits payable														$ 100,000	$ 100,000