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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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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Stockholders' Equity Stockholders' Equity - Schedule of Dividends (Details) - USD ($) $ / shares in Units, $ in Millions								3 Months Ended		9 Months Ended
	Nov. 06, 2017	Sep. 15, 2017	Aug. 07, 2017	Jun. 22, 2017	May 08, 2017	Mar. 28, 2017	Feb. 28, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Dividends Payable [Line Items]
Dividends per share (in dollars per share)			$ 0.09		$ 0.09		$ 0.09	$ 0.09	$ 0.08	$ 0.27	$ 0.24
Cash payment amount		$ 4.2		$ 4.2		$ 4.2				$ 12.6	$ 11.3
Subsequent Event
Dividends Payable [Line Items]
Dividends per share (in dollars per share)	$ 0.10