Income Tax Benefit (Provision) - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Tax Credit Carryforward [Line Items]
Statutory tax rate			39.60%	39.60%	35.00%
Current tax benefit or provision
Expected realization of net operating loss carryforwards			0	0	0
Income tax benefit result from decrease in net deferred tax liability		411,600,000	164,800,000
Valuation allowance against deferred tax assets	(103,900,000)	103,900,000	71,200,000
Net operating loss carryforwards			84,500,000
Net operating loss carryforwards begin to expire			2032-03
Capital loss carryforwards begin to expire			2017-03
Deferred tax asset			106,867,000	18,212,000
Capital Loss Carryforwards [Member]
Tax Credit Carryforward [Line Items]
Capital losses for tax purposes			$ 185,400,000