Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Millions	Mar. 31, 2018	Mar. 31, 2017
Class A Voting Common Shares
Common shares, no par value	$ 0	$ 0
Authorized common shares	500.0	500.0
Common shares, shares issued	81.8	81.1
Class B Non-Voting Common Shares
Common shares, no par value	$ 0	$ 0
Authorized common shares	500.0	500.0
Common shares, shares issued	129.3	126.4

Face amount per share of no-par value common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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