Shareholders' Equity and Noncontrolling Interests, Dividends (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	6 Months Ended
Apr. 24, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Shareholders' Equity and Noncontrolling Interests
Dividends declared per share (in dollars per share)	$ 0.23	$ 0.23	$ 0.19	$ 0.16	$ 0.42	$ 0.32
Dividends declared		$ 69.0		$ 48.8	$ 126.4	$ 97.8
Dividends paid		$ 57.4		$ 48.9	$ 115.5	$ 98.2

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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