Dividends on common stock: (Details) - USD ($) $ / shares in Units, $ in Thousands			6 Months Ended
Aug. 31, 2022	Aug. 04, 2022	Jun. 30, 2022	Jun. 30, 2021
Dividends on common stock and return of capital program
Quarterly dividend payment approved (per share)		$ 0.905
Dividends paid	$ 42,300		$ 83,153	$ 73,082

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

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