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

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Subsequent Events (Details) - $ / shares					3 Months Ended		9 Months Ended
Subsequent Events (Details) - $ / shares	Nov. 08, 2017	Aug. 09, 2017	May 09, 2017	Feb. 23, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Subsequent Events
Dividend declared (in dollars per share)		$ 0.48	$ 0.48	$ 0.48	$ 0.48	$ 0.48	$ 1.44	$ 1.44
Subsequent Events
Subsequent Events
Dividend declared (in dollars per share)	$ 0.48