Equity and dividends (Narrative) (Details) - USD ($)		1 Months Ended	3 Months Ended			6 Months Ended
	Dec. 08, 2020	Jul. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Dividends Payable [Line Items]
Preferred shares issued			0			0
Stock repurchased during period, shares			0		0	0	1,525,312
Stock repurchased during period, value							$ 53,170,000
Gain (Loss) from intra-entity foreign currency transactions			$ 1,095,000		$ 5,158,000	$ (2,559,000)	(2,334,000)
Subsequent Events [Member]
Dividends Payable [Line Items]
Dividends declared (USD per share)		$ 0.25
Dividends payable date		Sep. 15, 2021
Dividends, date of record		Aug. 25, 2021
Rouse Services LLC [Member]
Dividends Payable [Line Items]
Common shares issued (in shares)	312,193
Vesting period	3 years
Fair value of common shares (per share)	$ 71.09
Unrecognized share based continuing employment costs			$ 11,898,000		$ 0	$ 11,898,000	$ 0
Unrecognized share based continuing employment costs, weighted average period for recognition						1 year 8 months 12 days
Number of common shares restrictions have not yet vested						256,683
Shares forfeited				55,510		55,510