Shareholders' Equity, Dividends (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended	9 Months Ended
Sep. 30, 2016	Jul. 31, 2017	Oct. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Shareholders’ Equity
Dividends declared per common share (in dollars per share)	$ 0.14	$ 0.19	$ 0.16	$ 0.19	$ 0.14	$ 0.51	$ 0.42
Dividends paid				$ 48.8	$ 43.1	$ 147.1	$ 129.4
Dividends declared				$ 57.9	$ 43.2	$ 155.7	$ 129.5

Aggregate dividends declared 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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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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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=98514028&loc=d3e3291-108585

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