BUSINESS SEGMENTS - Income Before Taxes From Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Segment operating profit:	$ 17,798	$ 16,936	$ 32,835	$ 34,796
Net interest expense	(16,044)	(12,705)	(32,686)	(25,994)
Unallocated amounts	10,541	10,455	20,977	20,766
Income before taxes from continuing operations			13,715
Income before taxes from continuing operations	3,188	4,169	1,115	8,600
Postretirement Life Insurance [Member] \| Continuing Operations [Member]
Segment Reporting Information [Line Items]
Segment operating profit from continuing operations	29,780	27,329	59,011	55,360
Net interest expense	(16,044)	(12,705)	(32,686)	(25,994)
Unallocated amounts	10,541	10,455	20,977	20,766
Acquisition costs	(7)	0	(1,619)	0
Income before taxes from continuing operations	0	0	(2,614)	0
Income before taxes from continuing operations	3,188	4,169	1,115	8,600
Postretirement Life Insurance [Member] \| Continuing Operations [Member] \| Home And Building Products [Member]
Segment Reporting Information [Line Items]
Segment operating profit:	28,478	18,314	56,229	40,954
Postretirement Life Insurance [Member] \| Continuing Operations [Member] \| Telephonics [Member]
Segment Reporting Information [Line Items]
Segment operating profit:	$ 1,302	$ 9,015	$ 2,782	$ 14,406

Gross Profit from Continuing Operations

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- Definition

Amount of unallocated expense included in noninterest expense for the reportable segment during the period.

+ References

No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(7)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The net amount of operating interest income (expense).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.10)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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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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