Pension and Retirement Plans (Detail) - Changes of the benefit obligation, the plan assets and funded status of the plans (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 10,094	$ 9,473
Net amount recognized	11,098	9,406
U.S.
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	2,273	2,228
Foreign
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	8,825	7,178
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	45	59
Interest cost	839	747
Net amount recognized	10,053	8,549
Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	69	64
Net amount recognized	1,228	1,371
Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	45	59
Interest cost	770	683
Net amount recognized	8,825	7,178
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	10	0
Interest cost	43	35
Net amount recognized	1,045	857
Post Retirement \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	10	0
Interest cost	43	35
Net amount recognized	1,045	857
Post Retirement \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	0	0
Net amount recognized	0	0
Change in projected benefit obligation (“PBO”) \| Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	18,022	18,180
Service cost	45	59
Interest cost	839	747
Changes in actuarial assumptions	2,346	(584)
Foreign exchange impact	(389)	235
Benefits paid	(716)	(615)
Projected benefit obligation	20,147	18,022
Change in projected benefit obligation (“PBO”) \| Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,371	1,605
Service cost	0	0
Interest cost	69	64
Changes in actuarial assumptions	10	(76)
Foreign exchange impact		0
Benefits paid	(222)	(222)
Projected benefit obligation	1,228	1,371
Change in projected benefit obligation (“PBO”) \| Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	16,651	16,575
Service cost	45	59
Interest cost	770	683
Changes in actuarial assumptions	2,336	(508)
Foreign exchange impact	(389)	235
Benefits paid	(494)	(393)
Projected benefit obligation	18,919	16,651
Change in projected benefit obligation (“PBO”) \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	857	882
Service cost	10	0
Interest cost	43	35
Changes in actuarial assumptions	135	(60)
Foreign exchange impact	0	0
Benefits paid	0	0
Projected benefit obligation	1,045	857
Change in projected benefit obligation (“PBO”) \| Post Retirement \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	857	882
Service cost	10	0
Interest cost	43	35
Changes in actuarial assumptions	135	(60)
Foreign exchange impact		0
Benefits paid	0	0
Projected benefit obligation	1,045	857
Change in projected benefit obligation (“PBO”) \| Post Retirement \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	0	0
Service cost	0	0
Interest cost	0	0
Changes in actuarial assumptions	0	0
Foreign exchange impact	0	0
Benefits paid	0	0
Projected benefit obligation	0	0
Changes in fair value of plan assets:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			8,914
Fair value of plan assets	10,094	9,473	8,914
Changes in fair value of plan assets: \| Pension
Defined Benefit Plan Disclosure [Line Items]
Actual gain (loss) on plan assets	718	475
Company contributions	615	673
Foreign exchange impact	4	26
Benefits paid	(716)	(615)
Funded status	(10,053)	(8,549)
Net amount recognized	(10,053)	(8,549)
Changes in fair value of plan assets: \| Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Actual gain (loss) on plan assets	0	0
Company contributions	222	222
Foreign exchange impact	0	0
Benefits paid	(222)	(222)
Fair value of plan assets	0	0
Funded status	(1,228)	(1,371)
Net amount recognized	(1,228)	(1,371)
Changes in fair value of plan assets: \| Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,473	8,914
Actual gain (loss) on plan assets	718	475
Company contributions	393	451
Foreign exchange impact	4	26
Benefits paid	(494)	(393)
Fair value of plan assets	10,094	9,473
Funded status	(8,825)	(7,178)
Net amount recognized	(8,825)	(7,178)
Changes in fair value of plan assets: \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Actual gain (loss) on plan assets	0	0
Company contributions	0	0
Foreign exchange impact	0	0
Benefits paid	0	0
Fair value of plan assets	0	0
Funded status	(1,045)	(857)
Net amount recognized	(1,045)	(857)
Changes in fair value of plan assets: \| Post Retirement \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Actual gain (loss) on plan assets	0	0
Company contributions	0	0
Foreign exchange impact	0	0
Benefits paid	0	0
Fair value of plan assets	0	0
Funded status	(1,045)	(857)
Net amount recognized	(1,045)	(857)
Changes in fair value of plan assets: \| Post Retirement \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Actual gain (loss) on plan assets	0	0
Company contributions	0	0
Foreign exchange impact	0	0
Benefits paid	0	0
Fair value of plan assets	0	0
Funded status	0	0
Net amount recognized	$ 0	$ 0

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

-URI http://asc.fasb.org/extlink&oid=6504192

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(1)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6504226

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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Gain or Loss

-URI http://asc.fasb.org/extlink&oid=6514294

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Gain or Loss

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- Definition

The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ 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 (a)

-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 Projected Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6522206

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503904

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- Definition

The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

-URI http://asc.fasb.org/extlink&oid=6521376

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

-Paragraph 4

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Benefits

-URI http://asc.fasb.org/extlink&oid=6506267

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Benefits

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(6)

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- Definition

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

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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

Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency.

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The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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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.

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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

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-Publisher FASB

-Name Accounting Standards Codification

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

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