Common Shares, Redeemable Common Shares and Preferred Shares Common shares by class (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Class of Stock [Line Items]
Shares, Outstanding	41,347,394	42,717,484	44,502,222
Treasury Stock, Shares, Acquired	(3,972,974)	(4,165,582)
Shares sold	2,014,365	1,771,075
Stock subscription offering, employee cash purchases	13,662	152,800
Options exercised	574,857	456,969
Permanent equity [Member]
Class of Stock [Line Items]
Shares, Outstanding	32,848,308	33,529,474	35,110,432
Treasury Stock, Shares, Acquired	(2,560,912)	(3,020,253)
Shares sold	1,291,227	829,526
Stock subscription offering, employee cash purchases	13,662	152,800
Options exercised	574,857	456,969
Temporary equity [Member]
Class of Stock [Line Items]
Shares, Outstanding	8,499,086	9,188,010	9,391,790
Treasury Stock, Shares, Acquired	(1,412,062)	(1,145,329)
Shares sold	723,138	941,549
Stock subscription offering, employee cash purchases	0	0
Options exercised	0	0