Stock Repurchased and Retired During Period, Per Share

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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- Definition

Number of shares of common and preferred stock retired from treasury during the period.

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Share Capital - Changes in Number of Shares of Class A Stock Outstanding (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 15, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Dividends	$ 1.12	$ 0.12	$ 0.12	$ 0.12	$ 0.12	$ 0.12	$ 0.11	$ 0.11	$ 1.48	$ 0.46
Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Class A Stock outstanding, beginning of year				12,698,703				12,941,809	12,698,703	12,941,809
Issued pursuant to shared-based compensation plans									401,597	80,143
Repurchased and canceled pursuant to the stock buy-back									(718,522)	(323,249)
Class A Stock outstanding, end of year	12,381,778				12,698,703				12,381,778	12,698,703	12,941,809
Dividends									$ 1.48	$ 0.46	$ 0.44
New Program [Member] \| Common Class A [Member]
Class of Stock [Line Items]
Stock Repurchased and Retired During Period, Value									$ 15.0	$ 8.4
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Stock Repurchased and Retired During Period, Per Share									$ 20.94	$ 25.99
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	401,013				589,535				401,013	589,535		628,625