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Stockholders' Equity - Dividends (Details) - $ / shares	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016
Dividends Paid 1 [Member]
Dividends Payable [Line Items]
Cash dividend (in dollars per share)	$ 0.10			$ 0.07
Dividends Paid 2 [Member]
Dividends Payable [Line Items]
Cash dividend (in dollars per share)		$ 0.075			$ 0.065
Dividends Paid 3 [Member]
Dividends Payable [Line Items]
Cash dividend (in dollars per share)			$ 0.075			$ 0.05

X

- Definition

Aggregate dividends paid 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

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X

- Definition

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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