Derivatives and Hedging Activities - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Sep. 30, 2017
Derivatives, Fair Value [Line Items]
Asset Derivative	$ 490	$ 277
Liability Derivative	203	182
Interest rate swap - cash flow hedge \| Designated as hedging instrument \| Other Assets
Derivatives, Fair Value [Line Items]
Asset Derivative	287	95
Interest rate swap - cash flow hedge \| Designated as hedging instrument \| Other Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivative	0	0
Currency forward contract - non-designated hedge \| Not-designated hedge \| Other Assets
Derivatives, Fair Value [Line Items]
Asset Derivative	203	182
Currency forward contract - non-designated hedge \| Not-designated hedge \| Other Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivative	$ 203	$ 182

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant