Number of common shares purchased by shareholders.

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- Definition

Percentage of the entity's common stock outstanding owned by a related party.

+ References

No definition available.

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- Definition

Related party, percentage owned of entity.

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- Definition

Related Party Transaction, Maximum Expenses Reimbursable to Related Party

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No definition available.

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- Definition

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

+ References

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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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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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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Related Party Transactions (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 2015	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	May 21, 2018
Related Party Transaction [Line Items]
Common shares agreed to be purchased (in shares)	5,000,000
Common shares, no par value	$ 0
Related party expenses incurred				$ 0.8
Investment in equity method investees		$ 53.4	$ 20.6	16.8
Director
Related Party Transaction [Line Items]
Related party, ownership percentage of entity		100.00%
Related party transaction, amounts paid		$ 0.1	0.0
Equity Method Investees
Related Party Transaction [Line Items]
Related party expenses incurred		22.0	10.5	12.3
Atom Tickets \| Equity Method Investees
Related Party Transaction [Line Items]
Investment in equity method investees		$ 10.0	$ 0.0	7.9
Class A Voting Common Shares
Related Party Transaction [Line Items]
Common shares, no par value		$ 0	$ 0
Class A Voting Common Shares \| Subsequent Event \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Percentage of common stock outstanding held by Mark H. Rachesky					18.50%
Class B Non-Voting Common Shares
Related Party Transaction [Line Items]
Common shares, no par value		$ 0	$ 0
Class B Non-Voting Common Shares \| Subsequent Event \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Percentage of common stock outstanding held by Mark H. Rachesky					11.70%
Voting Agreement \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Maximum out-of-pocket expenses reimbursable			$ 1.6
Related party expenses incurred			0.5
Voting Agreement \| Director
Related Party Transaction [Line Items]
Maximum out-of-pocket expenses reimbursable			1.6
Related party expenses incurred			1.5
Other \| Director
Related Party Transaction [Line Items]
Related party expenses incurred		$ 5.6	$ 1.0
Maximum \| Director
Related Party Transaction [Line Items]
Related party transaction, amounts paid				$ 0.1