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, 2018	Sep. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 8,239
Fair value of plan assets	8,270	$ 8,239
Net amount recognized	6,508	6,978
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	395	350
Net amount recognized	5,188	5,723
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	40	38
Interest cost	47	44
Net amount recognized	1,320	1,255
Change in projected benefit obligation (“PBO”) \| Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	13,962	14,595
Service cost	0	0
Interest cost	395	350
Changes in actuarial assumptions	(172)	(995)
Foreign exchange impact	(364)	400
Benefits paid	362	388
Projected benefit obligation	13,459	13,962
Change in projected benefit obligation (“PBO”) \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,255	1,257
Service cost	40	38
Interest cost	47	44
Changes in actuarial assumptions	(24)	(84)
Projected benefit obligation	1,318	1,255
Changes in fair value of plan assets:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8,239	7,629
Fair value of plan assets	8,270	8,239
Changes in fair value of plan assets: \| Pension
Defined Benefit Plan Disclosure [Line Items]
Actual gain on plan assets	291	368
Company contributions	337	362
Foreign exchange impact	(235)	268
Benefits paid	362	388
Funded status \ net amount recognized	(5,189)	(5,723)
Changes in fair value of plan assets: \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Funded status \ net amount recognized	(1,318)	(1,255)
International
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized	4,603	5,046
International \| Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	370	321
Net amount recognized	4,603	5,046
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	13,285	13,766
Service cost	0	0
Interest cost	370	321
Changes in actuarial assumptions	(165)	(986)
Foreign exchange impact	(364)	400
Benefits paid	252	216
Projected benefit obligation	12,874	13,285
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	8,239	7,629
Actual gain on plan assets	291	368
Company contributions	227	190
Foreign exchange impact	(235)	268
Benefits paid	252	216
Fair value of plan assets	8,270	8,239
Funded status \ net amount recognized	(4,604)	(5,046)
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	1,905	1,932
Domestic \| Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	25	29
Net amount recognized	585	677
Domestic \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	40	38
Interest cost	47	44
Net amount recognized	1,320	1,255
Domestic \| Change in projected benefit obligation (“PBO”) \| Pension
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	677	829
Service cost	0	0
Interest cost	25	29
Changes in actuarial assumptions	(7)	(9)
Foreign exchange impact	0	0
Benefits paid	110	172
Projected benefit obligation	585	677
Domestic \| Change in projected benefit obligation (“PBO”) \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	1,255	1,257
Service cost	40	38
Interest cost	47	44
Changes in actuarial assumptions	(24)	(84)
Projected benefit obligation	1,318	1,255
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	110	172
Foreign exchange impact	0	0
Benefits paid	110	172
Fair value of plan assets	0	0
Funded status \ net amount recognized	(585)	(677)
Domestic \| Changes in fair value of plan assets: \| Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Funded status \ net amount recognized	$ (1,318)	$ (1,255)

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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-SubTopic 20
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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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-Name Accounting Standards Codification
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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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