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, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	May 05, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Dividends	$ 0.12	$ 0.12	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.46	$ 0.44
Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Class A Stock outstanding, beginning of year				12,941,809				13,139,203	12,941,809	13,139,203
Issued pursuant to shared-based compensation plans									80,143	38,728
Repurchased and canceled pursuant to the stock buy-back									(323,249)	(236,122)
Class A Stock outstanding, end of year	12,698,703				12,941,809				12,698,703	12,941,809	13,139,203
Dividends									$ 0.46	$ 0.44	$ 0.44
New Program [Member] \| Common Class A [Member]
Class of Stock [Line Items]
Stock Repurchased and Retired During Period, Value									$ 8.4	$ 5.9
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Stock Repurchased and Retired During Period, Per Share									$ 25.99	$ 24.96
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	589,535				272,784				589,535	272,784		666,192