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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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Stock Option And Stock Award Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,827,438	1,628,903	890,116	608,520
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		$ 0.1	$ 0.4
The grant-date fair value of stock option-based awards vested	$ 3.0	$ 0.5	$ 0.1
Stock options exercisable	1,287,792	360,218
Total stock options available for grant	484,835
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	376,440	0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	387,252
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Modification	71,402
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(82,214)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	0
Share Based Compensation Arrangement By Share Based Payment Award, non-option equity awards, Outstanding, Weighted AverageExercise Price	$ 11.64	$ 0
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, Grants in Period, Weighted Average Exercise Price	11.60
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, modification, Weighted Average Exercise Price	11.60
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, forfeited and expired, Weighted Average Exercise Price	11.39
Share-based Compensation Arrangements by Share-based Payment Award, non-option equity awards, exercised, Weighted Average Exercise Price	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested	$ 0.6
Payments of Dividends	$ 200.0
Dividends Payable, Amount Per Share	$ 5.97
Stock Option Based Awards [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost	$ 2.0
Weighted average period for the cost expected to be recognized	1 year 2 months 12 days
Non-Vested Restricted Stock And Other Stock-Based Awards
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	1 year 4 months 24 days
Stock Non-Option Based Awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost	$ 1.5
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	15.65	$ 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	0
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, Grants In Period, Exercise Price	10.75
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, modification, Exercise Price	10.75
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, forfeited and expired, Exercise Price	10.75
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, Excercised, Exercise Price	0
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	24.84	$ 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	19.64	$ 0
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, Grants In Period, Exercise Price	19.64
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, modification, Exercise Price	19.64
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, forfeited and expired, Exercise Price	19.64
Share Based Compensation Arrangements By Share Based Payment Award, non-option equity award, Excercised, Exercise Price	$ 0
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	57,385	26,389	17,153