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CONSOLIDATED STATEMENTS OF COMMON STOCK EQUITY (Parenthetical) - $ / shares | 12 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
Statement of Stockholders' Equity [Abstract] |  |  |
Cash dividends declared per share (in usd per share) | $ 0.975 | $ 0.915 | $ 0.855
Dividend Reinvestment Plan waiver discount feature (in shares) | 0 | 688,000 | 0

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- Definition Number of shares issued during the period from a DRP waiver discount feature. + References No definition available. + Details
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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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