Share-based Compensation Arrangement by Share-based Payment Award, Awards Exchanged in Period, Gross

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Awards Exchanged in Period, Weighted Average Exercise Price

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- Definition

Stock Repurchased And Retired During Period, Average Price Per Share

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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- Definition

Number of shares that have been repurchased and retired during the period.

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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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Capital Stock (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions			6 Months Ended	161 Months Ended
	Sep. 15, 2020	May 07, 2020	Sep. 30, 2020	Nov. 05, 2020	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
LGEC 2019 Performance Incentive Plan, number of additional shares authorized (in shares)	10.0
LGEC 2019 Performance Incentive Plan, number of shares authorized (in shares)	16.1
Repurchases of common shares, value			$ 1.0
Class A Voting Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized common shares (in shares)			500.0		500.0
Repurchases of common shares, shares			0.2
Repurchases of common shares, value			$ 1.0
Repurchases of common shares, weighted average repurchase price per share			$ 5.75
Class B Non-Voting Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized common shares (in shares)			500.0		500.0
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchases of common shares, value				$ 288.1
Share repurchase program, remaining authorized repurchase amount				$ 179.9
Options and SARs, existing \| Class A Voting Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards exchanged (in shares)		1.1
Options and SARs, existing \| Class B Non-Voting Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards exchanged (in shares)		4.3
Options and SARs, new \| Class A Voting Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards exchanged (in shares)		0.1
Awards exchanged, exercise price (in USD per share)		$ 7.70
Options and SARs, new \| Class B Non-Voting Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards exchanged (in shares)		0.8
Awards exchanged, exercise price (in USD per share)		$ 7.13