Share-Based Compensation and Benefit Plans (Narrative) (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)	May 17, 2018 shares
Total compensation cost for option and share awards	$ 14,200,000	$ 16,100,000	$ 15,300,000
Total capitalized compensation cost for option and share awards	$ 4,500,000	$ 3,800,000	3,400,000
Percentage Of Market Value Per Share At Which Shares Purchased Under Employee Share Purchase Plan	85.00%
EmployeeSharePurchasePlanMaximumAuthorizedAmountPerParticipant	$ 25,000
Share Awards Held In Employee Trust Shares | shares	1,100,000	1,200,000
Share Awards Held In Non Qualified Deferred Compensation Plan Shares	$ 8,900,000	$ 11,700,000
Cash Required By Plan Participants Upon Withdrawal	13,300,000	14,100,000
Defined Contribution Plan, Cost	$ 3,400,000	$ 3,300,000	3,400,000
Employee Share Purchase Program maximum shares available | shares	500,000
Share Awards Held In Non Qualified Deferred Compensation Plan Shares | shares	1,000,000	900,000
Trading Securities Held In Non Qualified Deferred Compensation Plan Value	$ 111,700,000	$ 125,600,000
Share Awards and Vesting [Member]
Total unrecognized compensation cost related to unvested options which is expected to be amortized	12,100,000
Fair value of shares vested	$ 19,400,000	$ 23,600,000	$ 18,700,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years
Maximum [Member] | Share Awards and Vesting [Member]
Vesting period, years	3 years
Two Thousand Eighteen Share Incentive Plan [Member]
Total fungible units to be issued | shares	5,900,000			9,700,000
Fungible Units To Full Value Award Conversion Ratio	3.45
Full Value award in the fungible unit conversion ratio | shares	1.0
Expiration value of option right or other award | shares	1.0
Common shares which could be granted pursuant to full value awards | shares	1,700,000