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EMPLOYEE BENEFIT PLANS - DEFINED CONTRIBUTION (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Defined Benefit Plan Disclosure [Line Items]
Defined contribution, company match of employee contribution	65.00%
Defined contribution plan, maximum employer contribution by percentage of employee salary	6.00%
Defined contribution plan, cost recognized	$ 2,900	$ 2,800	$ 2,600
Deferred compensation arrangement with individual, employer contribution	$ 781	$ 571	$ 461
NJRHS | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer contribution for employees not qualifying for the defined benefit plan	3.00%
NJRHS | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer contribution for employees not qualifying for the defined benefit plan	4.00%

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Defined Contribution Plan, Company Match of Employee Contribution

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Defined Contribution Plan, Employer Contribution For Employees Not Qualify For The Defined Benefit Plan

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- Definition

Amount of cost for defined contribution plan.

+ References

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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