Stock Option And Stock Award Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,125,944	2,827,438	1,628,903	890,116
Options may be granted to purchase specified number of common shares under stock option plan, maximum term	10 years
The total intrinsic value of stock options exercised	$ 0.2		$ 0.1
The grant-date fair value of stock option-based awards vested	$ 3.5	$ 3.0	0.5
Stock options exercisable	1,762,190	1,287,792
Total stock options available for grant	910,420
Share-based Payment Arrangement, Expense		$ 0.1	$ 1.3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested	(521,601)	376,440	0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	164,464	387,252
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Modification	(10,043)	71,402
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(9,260)	(82,214)
Share Based Compensation Arrangement By Share Based Payment Award, non-option equity awards, Outstanding, Weighted AverageExercise Price	$ 13.55	$ 11.64	$ 0
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, Grants in Period, Weighted Average Exercise Price	16.37	11.60
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, modification, Weighted Average Exercise Price	13.01	11.60
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, forfeited and expired, Weighted Average Exercise Price	$ 13.87	$ 11.39
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested	$ 0.1	$ 0.6
Payments of Dividends	$ 200.0
Dividends Payable, Amount Per Share	$ 5.97
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 0.4
Stock Option Based Awards [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost	$ 1.7
Weighted average period for the cost expected to be recognized	7 months 6 days
Non-Vested Restricted Stock And Other Stock-Based Awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost	$ 2.6
Weighted average period for the cost expected to be recognized	1 year 6 months
Minimum
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, Options, Outstanding, Exercise Price	$ 10.75	$ 10.75	15.65	$ 15.65
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, non-option equity awards, Outstanding, Exercise Price	10.75	10.75	0
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, Grants In Period, Exercise Price	16.37	10.75
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, modification, Exercise Price	10.75	10.75
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, forfeited and expired, Exercise Price	10.75	10.75
Maximum
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, Options, Outstanding, Exercise Price	22.49	22.49	24.84	$ 24.84
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, non-option equity awards, Outstanding, Exercise Price	16.37	19.64	$ 0
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, Grants In Period, Exercise Price	16.37	19.64
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, modification, Exercise Price	16.37	19.64
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, forfeited and expired, Exercise Price	$ 15.25	$ 19.64
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	11,616	57,385	26,389

Options may be granted to purchase specified number of common shares under stock option plan, maximum term.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Net number of non-option equity instruments granted to participants.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options outstanding, including both vested and non-vested options.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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