Segment Information (Reconciliation Of Total Segment Profit (Loss) To The Company's Loss Before Income Taxes) (Details) (USD $)	3 Months Ended				6 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Company's total segment profit	$ 129,269,000		$ (4,389,000)		$ 157,004,000		$ 37,909,000
Less:
Shared services and corporate expenses	(26,003,000)	[1]	(14,944,000)	[1]	(58,789,000)	[1]	(28,009,000)	[1]
Depreciation and amortization	(2,115,000)		(681,000)		(4,220,000)		(1,915,000)
Interest expense	(23,285,000)		(17,569,000)		(50,775,000)		(33,904,000)
Interest and other income	1,029,000		928,000		1,979,000		1,370,000
Gain on sale of asset disposal group	0		10,967,000		0		10,967,000
Gain (loss) on extinguishment of debt	(1,000,000)		(436,000)		(9,159,000)		(967,000)
Equity interests income (loss)	1,755,000		1,889,000		1,610,000		1,849,000
Income (loss) before income taxes	79,650,000		(24,235,000)		37,650,000		(12,700,000)
Stock-based compensation expense	6,899,000		2,381,000		16,648,000		4,987,000
(Benefit) charge related to shareholder activist matter							(2,000,000)
Summit Entertainment, LLC [Member]
Less:
Severance and transaction costs	$ 300,000				$ 2,000,000

[1] Includes share-based compensation expense of $6.9 million and $16.6 million for the three and six months ended September 30, 2012, respectively, and $2.4 million and $5.0 million for the three and six months ended September 30, 2011, respectively. The three and six months ended September 30, 2012 also includes severance and transaction costs related to the acquisition of Summit of $0.3 million and $2.0 million, respectively. The six months ended September 30, 2011 includes a benefit for charges associated with a shareholder activist matter of $2.0 million related to a negotiated settlement with a vendor of costs incurred and recorded in fiscal year 2011, and insurance recoveries of related litigation offset by other costs.