The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Goodwill (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017	Jul. 01, 2017
Segment Reporting Information [Line Items]
Goodwill deductible for tax purposes	$ 141,511	$ 139,581
Neptune Benson Reporting Unit [Member]
Segment Reporting Information [Line Items]
Reporting unit, percentage of fair value in excess of carrying amount			3.00%