Pension and Retirement Plans (Detail) - Amounts recognized in the consolidated balance sheet (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	$ (11,098)	$ (9,406)
Deferred tax	(364)cspi_DefinedBenefitPlanDeferredTax	80cspi_DefinedBenefitPlanDeferredTax
Accumulated other comprehensive income	5,429	3,710
Net amount recognized	(6,033)cspi_NetAmountRecognized	(5,616)cspi_NetAmountRecognized
Accumulated benefit obligation	(21,071)	(18,769)
Foreign
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(8,825)	(7,178)
Deferred tax	(531)	(188)
Accumulated other comprehensive income	5,419	3,895
Net amount recognized	(3,937)	(3,471)
Accumulated benefit obligation	(18,798)	(16,541)
U.S.
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(2,273)	(2,228)
Deferred tax	167	268
Accumulated other comprehensive income	10	(185)
Net amount recognized	(2,096)	(2,145)
Accumulated benefit obligation	(2,273)	(2,228)
Pension
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(10,053)	(8,549)
Deferred tax	(509)	(159)
Accumulated other comprehensive income	5,433	3,896
Net amount recognized	(5,129)	(4,812)
Accumulated benefit obligation	(20,026)	(17,912)
Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(8,825)	(7,178)
Deferred tax	(531)	(188)
Accumulated other comprehensive income	5,419	3,895
Net amount recognized	(3,937)	(3,471)
Accumulated benefit obligation	(18,798)	(16,541)
Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(1,228)	(1,371)
Deferred tax	22	29
Accumulated other comprehensive income	14	1
Net amount recognized	(1,192)	(1,341)
Accumulated benefit obligation	(1,228)	(1,371)
Post Retirement
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	(1,045)	(857)
Deferred tax	145	239
Accumulated other comprehensive income	(4)	(186)
Net amount recognized	(904)	(804)
Accumulated benefit obligation	(1,045)	(857)
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	(1,045)	(857)
Deferred tax	145	239
Accumulated other comprehensive income	(4)	(186)
Net amount recognized	(904)	(804)
Accumulated benefit obligation	$ (1,045)	$ (857)

Deferred Tax affect related to define benefit plan - unrealized actuarial gain/loss in other comprehensive Income

No definition available.

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- Definition

Projected Benefit Obligation of defined benefit plans, net of unrealized losses recorded in accumulated comprehensive income

+ References

No definition available.

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- Definition

The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

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-Publisher FASB

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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