The amount of the cost recognized during the period for defined contribution plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

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.

+ References

No definition available.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

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Pension Plan and Retirement Benefits - Defined Contribution Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
401(k)
Defined Contribution Plans
Expenses associated with plan	$ 1,652	$ 1,598	$ 1,436
401(k) \| Employees with exceptions
Defined Contribution Plans
Percentage employer matches of the employee's percentage contribution matched.	50.00%
401(k) \| Employees with exceptions \| Maximum
Defined Contribution Plans
Percentage of employees' gross pay for which the employer contributes a matching contribution	3.00%
401(k) \| Certain employees not eligible for U.S. pension plan
Defined Contribution Plans
Percentage employer matches of the employee's percentage contribution matched.	60.00%
401(k) \| Certain employees not eligible for U.S. pension plan \| Maximum
Defined Contribution Plans
Percentage of employees' gross pay for which the employer contributes a matching contribution	6.00%
Profit sharing plans
Defined Contribution Plans
Expenses associated with plan	$ 0	$ 0	$ 0