Pension and Retirement Plans (Detail) - Components of net periodic benefit costs (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in minimum liability included in other comprehensive income (loss)	$ 2,164	$ (665)
U.S.
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in minimum liability included in other comprehensive income (loss)	296	23
Foreign
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in minimum liability included in other comprehensive income (loss)	1,868	(688)
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	45	59
Interest cost	839	747
Expected return on plan assets	(472)	(410)
Prior service gains	0	0
Amortization of net (gain)/loss	84	165
Net periodic benefit cost	496	561
Increase (decrease) in minimum liability included in other comprehensive income (loss)	1,888	(792)
Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	69	64
Expected return on plan assets	0	0
Prior service gains	0	0
Amortization of net (gain)/loss	(9)	24
Net periodic benefit cost	60	88
Increase (decrease) in minimum liability included in other comprehensive income (loss)	20	(104)
Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	45	59
Interest cost	770	683
Expected return on plan assets	(472)	(410)
Prior service gains	0	0
Amortization of net (gain)/loss	93	141
Net periodic benefit cost	436	473
Increase (decrease) in minimum liability included in other comprehensive income (loss)	1,868	(688)
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	10	0
Interest cost	43	35
Expected return on plan assets	0	0
Prior service gains	0	0
Amortization of net (gain)/loss	(142)	(183)
Net periodic benefit cost	(89)	(148)
Increase (decrease) in minimum liability included in other comprehensive income (loss)	276	127
Post Retirement \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	10	0
Interest cost	43	35
Expected return on plan assets	0	0
Prior service gains	0	0
Amortization of net (gain)/loss	(142)	(183)
Net periodic benefit cost	(89)	(148)
Increase (decrease) in minimum liability included in other comprehensive income (loss)	276	127
Post Retirement \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	0	0
Expected return on plan assets	0	0
Prior service gains	0	0
Amortization of net (gain)/loss	0	0
Net periodic benefit cost	0	0
Increase (decrease) in minimum liability included in other comprehensive income (loss)	$ 0	$ 0

The amount of gains or losses recognized in net periodic benefit cost.

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512136

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- 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

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i-k)

-URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580

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