Shareholders' Equity - Schedule of Shares Issued in Connection with Dividend Reinvestment and Stock Purchase Plan (Details) - USD ($)	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Equity [Abstract]
Amounts received	$ 72,175,797	$ 48,404,556	$ 38,090,334
Less: Dividend reinvestments	8,369,146	8,489,169	7,624,528
Amounts received, net	$ 63,806,651	$ 39,915,387	$ 30,465,806
Number of Shares Issued	6,515,750	4,975,500	4,296,075

Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Name:	us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration