Stock Compensation Plans and Other Employee Benefit Plans (Summary of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended	72 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021
Common Shares
Common shares, outstanding at beginning of the period (in shares)	520,663	755,332	795,014
Common shares, granted (in shares)	0	0	0	0
Common shares, options outstanding in acquired plans (in shares)			106,748
Common shares, exercised (in shares)	(326,626)	(229,061)	(146,430)
Common shares, forfeited or canceled (in shares)	(590)	(5,608)	0
Common shares, outstanding at end of the period (in shares)	193,447	520,663	755,332	193,447
Common shares, exercisable (in shares)	191,898	512,762	735,396	191,898
Common shares, vested or expected to vest (in shares)	193,447			193,447
Weighted Average Strike Price
Weighted average strike price, outstanding at beginning of period (usd per share)	$ 42.47	$ 42.43	$ 42.25
Weighted average strike price, granted (usd per share)	0	0	0
Weighted average strike price, options outstanding in acquired plans (in usd per share)			38.83
Weighted average strike price, exercised (usd per share)	42.97	42.29	38.84
Weighted average strike price, forfeited or canceled (usd per share)	46.86	44.34	0
Weighted average strike price, outstanding at end of period (usd per share)	41.62	42.47	42.43	$ 41.62
Weighted average strike price, exercisable (in dollars per share)	41.57	$ 42.46	$ 42.42	41.57
Weighted average strike price, vested or expected to vest (in dollars per share)	$ 41.62			$ 41.62
Stock Options Additional Disclosures
Remaining contractual term, outstanding	1 year 4 months 24 days	1 year 10 months 24 days	2 years 9 months 18 days
Remaining contractual term, exercisable	1 year 3 months 18 days	1 year 9 months 18 days	2 years 8 months 12 days
Remaining contractual term, vested or expected to vest	1 year 4 months 24 days
Intrinsic value, outstanding	$ 9,518	$ 9,694	$ 21,503	$ 9,518
Intrinsic value, exercisable	9,451	$ 9,555	$ 20,947	9,451
Intrinsic value, vested or expected to vest	$ 9,518			$ 9,518

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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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