Reconciliation of Income Taxes Computed at U.S Federal Statutory Tax rates to Income Tax Expense (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Reconciliation Of Statutory Federal Tax Rate [Line Items]
Tax benefit (expense) at U.S. statutory rates		$ 9,663	$ 3,532	$ 11,019
State tax		9	86	(5,370)
Warrant liability costs		(4,803)	5,803	(3,320)
Equity compensation		(2)	138	(837)
(Increase) decrease in valuation allowance		(4,230)	(9,082)	14,914
Revaluation of deferred taxes		0	0	(15,870)
Other		(638)	(478)	(537)
Income tax expense		$ (1)	$ (1)	$ (1)
Tax benefit (expense) at U.S. statutory rates	21.00%	21.00%	21.00%	28.00%	34.00%
State tax		0.00%	1.00%	(13.00%)
Warrant liability costs		(10.00%)	35.00%	(8.00%)
Equity compensation		0.00%	1.00%	(2.00%)
(Increase) decrease in valuation allowance		(9.00%)	(54.00%)	37.00%
Revaluation of deferred taxes		0.00%	0.00%	(40.00%)
Other		(1.00%)	(3.00%)	(1.00%)
Effective Income Tax Rate, Continuing Operations, Total		0.00%	0.00%	0.00%

Effective income tax rate reconciliation revaluation of deferred taxes.

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Amount of difference between Expected Income Tax Benefit(Expense),Reported Income Tax Benefit (Expense) computed by Applying Domestic Statutory rate to pre tax Income(Loss) from operation in respect of Expenses Attributable to warrants

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Percentage difference between reported Income tax Benefit (Expense) and Expected Income Tax Benefit (Expense) Computed By Applying Domestic Statutory rate to pre tax Income(Loss) from operation in respect of Expenses Attributable to warrants Attributable to pre tax Loss from continuing Operations

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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