Aggregate dividends paid during the period for each share of common stock outstanding.

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

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Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Dividends (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended		6 Months Ended
	Dec. 05, 2016	Nov. 07, 2016	Sep. 06, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Subsequent Event [Line Items]
Dividends declared per common share (in USD per share)				$ 0.3600	$ 0.3580	$ 0.7195	$ 0.7155
Total amount of dividend payment			$ 77.7			$ 154.9
Dividend per share paid during period			$ 0.3600			$ 0.7195
Subsequent Event
Subsequent Event [Line Items]
Dividends declared per common share (in USD per share)		$ 0.3605
Total amount of dividend payment	$ 80.0