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Equity and dividends (Additional Information) (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 31, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Dividends Payable [Line Items]
Preferred shares issued		0		0
Stock repurchased during period, shares		0	1,223,674	1,525,312	1,223,674
Stock repurchased during period, value			$ 42,012,000	$ 53,170,000	$ 42,012,000
Intra-entity foreign currency transactions		$ 5,158,000	$ 2,508,000	$ (2,334,000)	$ 1,653,000
Subsequent Events [Member]
Dividends Payable [Line Items]
Dividends declared (usd per share)	$ 0.22
Dividends payable date	Sep. 16, 2020
Dividends, date of record	Aug. 26, 2020