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.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

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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)
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Shareholder's Equity - Distribution to Common Shareholders (Details) - USD ($) $ / shares in Units, $ in Thousands						9 Months Ended
	Nov. 16, 2017	Oct. 12, 2017	Aug. 17, 2017	May 18, 2017	Feb. 21, 2017	Sep. 30, 2017	Sep. 30, 2016
Subsequent Event [Line Items]
Distribution to common shareholders (in dollars per share)			$ 0.39	$ 0.39	$ 0.39
Distribution to common shareholders			$ 92,648	$ 92,642	$ 92,642	$ 277,932	$ 277,846
Subsequent Event
Subsequent Event [Line Items]
Distributions to common shareholders declared (in dollars per share)		$ 0.39
Distributions to common shareholders payable		$ 92,676
Scenario, Forecast
Subsequent Event [Line Items]
Distribution to common shareholders (in dollars per share)	$ 0.39
Distribution to common shareholders	$ 92,676