Net Periodic Pension Cost (Detail) (USD $) In Thousands	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 216	$ 100	$ 100
Interest cost	796	775	702
Expected return on assets	(764)	(604)	(709)
Amortization of losses	458	327	89
Settlement loss			888
Net periodic pension cost	$ 706	$ 598	$ 1,070

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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+ Details

- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References+ Details

- Definition

The amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

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+ Details

- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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+ Details