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.

+ Details

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- Definition

Amount of general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

No definition available.

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- Definition

Related Party Transaction, Maximum Expenses Reimbursable to Related Party

+ References

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 percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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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=66902209&loc=d3e3213-108585

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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, 2017	Mar. 31, 2016	Mar. 31, 2015	May 23, 2017
Related Party Transaction [Line Items]
Certain costs related to registration and offering of the Company's common shares offered by MHR Affiliates			$ 0.8	$ 1.0
Common shares agreed to be purchased (in shares)	5,000,000
Common shares, no par value	$ 0	$ 0	$ 0
Investment in equity method investees		$ 20.6	$ 16.8	52.7
Equity Method Investees
Related Party Transaction [Line Items]
Related party expenses incurred		$ 10.5	12.3	13.9
Atom Tickets
Related Party Transaction [Line Items]
Investment in equity method investees			7.9	4.3
Equity method investment, ownership percentage		15.00%
Atom Tickets \| Equity Method Investees
Related Party Transaction [Line Items]
Investment in equity method investees			$ 7.9	$ 4.3
Equity method investment, ownership percentage		15.00%
Class A Voting Shares
Related Party Transaction [Line Items]
Common shares, no par value		$ 0	$ 0
Class A Voting Shares \| Subsequent Event \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Percentage of common stock outstanding held by Mark H. Rachesky					18.70%
Class B Non-Voting Shares
Related Party Transaction [Line Items]
Common shares, no par value		$ 0	$ 0
Class B Non-Voting Shares \| Subsequent Event \| Chairman of the Board of Directors
Related Party Transaction [Line Items]
Percentage of common stock outstanding held by Mark H. Rachesky					12.20%
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		$ 1.0