Pension and Retirement Plans (Detail) - Changes of the benefit obligation, the plan assets and funded status of the plans - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 10,094
Fair value of plan assets	9,301	$ 10,094
Net amount recognized	10,685	11,098
U.S.
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	2,007	2,273
Foreign
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	8,678	8,825
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	56	45
Interest cost	686	839
Net amount recognized	9,700	10,053
Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	52	69
Net amount recognized	1,022	1,228
Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	56	45
Interest cost	634	770
Net amount recognized	8,678	8,825
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	34	10
Interest cost	44	43
Net amount recognized	985	1,045
Post Retirement \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	34	10
Interest cost	44	43
Net amount recognized	985	1,045
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	20,147	18,022
Service cost	56	45
Interest cost	687	839
Changes in actuarial assumptions	296	2,346
Foreign exchange impact	(1,534)	(389)
Benefits paid	(651)	(716)
Projected benefit obligation	19,001	20,147
Change in projected benefit obligation (“PBO”) \| Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,228	1,371
Service cost	0	0
Interest cost	52	69
Changes in actuarial assumptions	(8)	10
Foreign exchange impact	0	0
Benefits paid	(250)	(222)
Projected benefit obligation	1,022	1,228
Change in projected benefit obligation (“PBO”) \| Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	18,919	16,651
Service cost	56	45
Interest cost	635	770
Changes in actuarial assumptions	304	2,336
Foreign exchange impact	(1,534)	(389)
Benefits paid	(401)	(494)
Projected benefit obligation	17,979	18,919
Change in projected benefit obligation (“PBO”) \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,045	857
Service cost	34	10
Interest cost	44	43
Changes in actuarial assumptions	(138)	135
Foreign exchange impact	0	0
Benefits paid	0	0
Projected benefit obligation	985	1,045
Change in projected benefit obligation (“PBO”) \| Post Retirement \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,045	857
Service cost	34	10
Interest cost	44	43
Changes in actuarial assumptions	(138)	135
Foreign exchange impact	0	0
Benefits paid	0	0
Projected benefit obligation	985	1,045
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	10,094	9,473
Fair value of plan assets	9,301	10,094
Changes in fair value of plan assets: \| Pension
Defined Benefit Plan Disclosure [Line Items]
Actual gain (loss) on plan assets	(117)	718
Company contributions	649	615
Foreign exchange impact	(673)	4
Benefits paid	(652)	(716)
Funded status	(9,700)	(10,053)
Net amount recognized	(9,700)	(10,053)
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	251	222
Foreign exchange impact	0	0
Benefits paid	(251)	(222)
Fair value of plan assets	0	0
Funded status	(1,022)	(1,228)
Net amount recognized	(1,022)	(1,228)
Changes in fair value of plan assets: \| Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10,094	9,473
Actual gain (loss) on plan assets	(117)	718
Company contributions	398	393
Foreign exchange impact	(673)	4
Benefits paid	(401)	(494)
Fair value of plan assets	9,301	10,094
Funded status	(8,678)	(8,825)
Net amount recognized	(8,678)	(8,825)
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	(985)	(1,045)
Net amount recognized	(985)	(1,045)
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	(985)	(1,045)
Net amount recognized	(985)	(1,045)
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=58740216&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

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-Publisher FASB
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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.

+ References

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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

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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.

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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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No definition available.

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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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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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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

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-Publisher FASB
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