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EMPLOYEE BENEFIT PLANS - DEFINED CONTRIBUTION (Details) - USD ($) $ in Thousands | 12 Months Ended
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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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- Definition Defined Contribution Plan, Company Match of Employee Contribution + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Contribution For Employees Not Qualify For The Defined Benefit Plan + References No definition available. + Details
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- Definition Defined Contribution Plan, Maximum Employer Contribution by Percentage of Employee Salary + References No definition available. + Details
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- Definition Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement. + References No definition available. + Details
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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. + Details
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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 + Details
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