Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

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

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Subsequent events (Details) - $ / shares			3 Months Ended		6 Months Ended
Subsequent events (Details) - $ / shares	Jan. 21, 2020	Oct. 16, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Dividends [Abstract]
Common stock, dividends declared (in dollars per share)			$ 0.11	$ 0.10	$ 0.22	$ 0.20
2020 Annual Dividend [Member]
Dividends [Abstract]
Common stock, dividends declared (in dollars per share)		$ 0.44
Subsequent Event [Member] \| 2020 Q2 Dividend [Member]
Dividends [Abstract]
Dividends payable, date declared	Jan. 21, 2020
Common stock, dividends declared (in dollars per share)	$ 0.11
Dividends payable, date of record	Feb. 14, 2020
Dividends payable, date paid	Feb. 28, 2020
Subsequent Event [Member] \| 2020 Annual Dividend [Member]
Dividends [Abstract]
Common stock, dividends declared (in dollars per share)	$ 0.44