Recent Accounting Pronouncements - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
Dec. 31, 2017	Sep. 30, 2018
Investments, Owned, Federal Income Tax Note [Line Items]
Tax Cuts and Jobs Act of 2017, change in tax rate, deferred tax asset, income tax expense (benefit)	$ 548,000
Tax Cuts and Jobs Act of 2017, change in tax rate, income tax expense (benefit)	$ 551,000
Forecast
Investments, Owned, Federal Income Tax Note [Line Items]
Statutory tax rate		24.50%

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration