Pension and Retirement Plans (Detail) - Amounts recognized in the consolidated balance sheet - USD ($) $ in Thousands	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	$ (10,685)	$ (11,098)
Deferred tax	(301)	(364)
Accumulated other comprehensive income	5,561	5,429
Net amount recognized	(5,425)	(6,033)
Accumulated benefit obligation	(19,873)	(21,071)
Foreign
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(8,678)	(8,825)
Deferred tax	(490)	(531)
Accumulated other comprehensive income	5,623	5,419
Net amount recognized	(3,545)	(3,937)
Accumulated benefit obligation	(17,866)	(18,798)
U.S.
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(2,007)	(2,273)
Deferred tax	189	167
Accumulated other comprehensive income	(62)	10
Net amount recognized	(1,880)	(2,096)
Accumulated benefit obligation	(2,007)	(2,273)
Pension
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(9,700)	(10,053)
Deferred tax	(466)	(509)
Accumulated other comprehensive income	5,634	5,433
Net amount recognized	(4,532)	(5,129)
Accumulated benefit obligation	(18,888)	(20,026)
Pension | Foreign
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(8,678)	(8,825)
Deferred tax	(490)	(531)
Accumulated other comprehensive income	5,623	5,419
Net amount recognized	(3,545)	(3,937)
Accumulated benefit obligation	(17,866)	(18,798)
Pension | U.S.
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(1,022)	(1,228)
Deferred tax	24	22
Accumulated other comprehensive income	11	14
Net amount recognized	(987)	(1,192)
Accumulated benefit obligation	(1,022)	(1,228)
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(985)	(1,045)
Deferred tax	165	145
Accumulated other comprehensive income	(73)	(4)
Net amount recognized	(893)	(904)
Accumulated benefit obligation	(985)	(1,045)
Post Retirement | Foreign
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	0	0
Deferred tax	0	0
Accumulated other comprehensive income	0	0
Net amount recognized	0	0
Accumulated benefit obligation	0	0
Post Retirement | U.S.
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(985)	(1,045)
Deferred tax	165	145
Accumulated other comprehensive income	(73)	(4)
Net amount recognized	(893)	(904)
Accumulated benefit obligation	$ (985)	$ (1,045)