Retirement Benefit Plans - Net Plan Assets Recognized in the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016
Reconciliation of funded status:
Plans in which Benefit Obligations Exceed Assets at September 30,	$ (6,230)	$ (8,387)
Amounts recognized in accumulated other comprehensive loss:
Net loss, Plans in which Benefit Obligations Exceed Assets	8,406	10,926
Net amount recognized in the consolidated balance sheets, Plans in which Benefit Obligations Exceed Assets	2,176	2,539
Amounts recognized in the consolidated balance sheets are:
Plans in which Benefit Obligations Exceed Assets at September 30,	(6,230)	(8,387)
Accumulated other comprehensive loss pretax, Plans in which Benefit Obligations Exceed Assets	8,406	10,926
Accrued liabilities
Reconciliation of funded status:
Plans in which Benefit Obligations Exceed Assets at September 30,	(46)	(46)
Amounts recognized in the consolidated balance sheets are:
Plans in which Benefit Obligations Exceed Assets at September 30,	(46)	(46)
Pension liability
Reconciliation of funded status:
Plans in which Benefit Obligations Exceed Assets at September 30,	(6,184)	(8,341)
Amounts recognized in the consolidated balance sheets are:
Plans in which Benefit Obligations Exceed Assets at September 30,	$ (6,184)	$ (8,341)

Defined benefit plan pension plans with accumulated benefit obligations in excess of plan aggregate benefit obligation accumulated other comprehensive income net gains losses after tax.

No definition available.

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- Definition

Defined benefit plans with benefit obligations in excess of plan assets aggregate benefit obligation accumulated other comprehensive income before tax.

+ References

No definition available.

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- Definition

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of benefit obligation for defined benefit plan with benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920

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