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)
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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=28358313&loc=d3e6935-107765

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Glossary Current Liabilities
-URI http://asc.fasb.org/extlink&oid=6509677

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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.

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No definition available.

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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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-Name Accounting Standards Codification
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Shareholder's Equity - Distribution to Common Shareholders (Details) - USD ($) $ / shares in Units, $ in Thousands					6 Months Ended
	Aug. 17, 2017	Jul. 12, 2017	May 18, 2017	Feb. 21, 2017	Jun. 30, 2017	Jun. 30, 2016
Dividends Payable [Line Items]
Distribution to common shareholders (in dollars per share)			$ 0.39	$ 0.39
Distribution to common shareholders			$ 92,642	$ 92,642	$ 185,284	$ 185,228
Subsequent Event
Dividends Payable [Line Items]
Distribution to common shareholders declared per share (in dollars per share)		$ 0.39
Distribution to common shareholders payable		$ 92,648
Scenario, Forecast
Dividends Payable [Line Items]
Distribution to common shareholders	$ 92,660
Distribution to common shareholders declared per share (in dollars per share)	$ 0.39