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, 2017	Sep. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 7,629
Fair value of plan assets	8,239	$ 7,629
Net amount recognized	12,352	14,022
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	41	35
Interest cost	415	614
Net amount recognized	11,097	12,765
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	38	27
Interest cost	44	42
Net amount recognized	1,255	1,257
Change in projected benefit obligation (“PBO”) \| Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	20,393	19,001
Service cost	42	35
Interest cost	415	614
Changes in actuarial assumptions	(1,591)	3,968
Foreign exchange impact	651	(2,069)
Benefits paid	574	1,156
Projected benefit obligation	19,336	20,393
Change in projected benefit obligation (“PBO”) \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,257	985
Service cost	38	27
Interest cost	44	42
Changes in actuarial assumptions	(84)	203
Projected benefit obligation	1,255	1,257
Changes in fair value of plan assets:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,629	9,301
Fair value of plan assets	8,239	7,629
Changes in fair value of plan assets: \| Pension
Defined Benefit Plan Disclosure [Line Items]
Actual gain on plan assets	368	111
Company contributions	548	662
Foreign exchange impact	268	(1,289)
Benefits paid	574	1,156
Funded status \ net amount recognized	(11,097)	(12,764)
Changes in fair value of plan assets: \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Funded status \ net amount recognized	(1,255)	(1,257)
International
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	10,420	11,936
International \| Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	41	35
Interest cost	386	571
Net amount recognized	10,420	11,936
International \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	0	0
Net amount recognized	0	0
International \| Change in projected benefit obligation (“PBO”) \| Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	19,564	17,979
Service cost	42	35
Interest cost	386	571
Changes in actuarial assumptions	(1,582)	3,948
Foreign exchange impact	651	(2,069)
Benefits paid	402	900
Projected benefit obligation	18,659	19,564
International \| Change in projected benefit obligation (“PBO”) \| Post Retirement
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
Projected benefit obligation	0	0
International \| Changes in fair value of plan assets: \| Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,629	9,301
Actual gain on plan assets	368	111
Company contributions	376	406
Foreign exchange impact	268	(1,289)
Benefits paid	402	900
Fair value of plan assets	8,239	7,629
Funded status \ net amount recognized	(10,420)	(11,935)
International \| Changes in fair value of plan assets: \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Funded status \ net amount recognized	0	0
Domestic
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	1,932	2,086
Domestic \| Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	29	43
Net amount recognized	677	829
Domestic \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	38	27
Interest cost	44	42
Net amount recognized	1,255	1,257
Domestic \| Change in projected benefit obligation (“PBO”) \| Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	829	1,022
Service cost	0	0
Interest cost	29	43
Changes in actuarial assumptions	(9)	20
Foreign exchange impact	0	0
Benefits paid	172	256
Projected benefit obligation	677	829
Domestic \| Change in projected benefit obligation (“PBO”) \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,257	985
Service cost	38	27
Interest cost	44	42
Changes in actuarial assumptions	(84)	203
Projected benefit obligation	1,255	1,257
Domestic \| Changes in fair value of plan assets: \| Pension
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Actual gain on plan assets	0	0
Company contributions	172	256
Foreign exchange impact	0	0
Benefits paid	172	256
Fair value of plan assets	0	0
Funded status \ net amount recognized	(677)	(829)
Domestic \| Changes in fair value of plan assets: \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Funded status \ net amount recognized	$ (1,255)	$ (1,257)

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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