Stockholders' Equity - Summary of common shareholders' equity - Parentheticals (Details) - $ / shares	Sep. 30, 2019	Jun. 30, 2019	May 15, 2019	Sep. 30, 2018	Jun. 30, 2018
Shareholders' Equity
Dividends Payable, Amount Per Share	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Name:	us-gaap_DividendsPayableAmountPerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant