Income Taxes (Tables)

12 Months Ended

Apr. 30, 2013

Income Taxes

Schedule of reconciliation of income tax expense computed using the U.S. federal statutory rates to actual income tax expense

	Year Ended April 30,
	2013			2012			2011
U.S. federal statutory income tax rate		35.0	%		35.0	%		35.0	%
State and local income taxes, net of federal benefit		(9.6	)		(0.3	)		1.1
R&D and other tax credits		(29.6	)		(3.4	)		(11.3	)
Other		7.4			(1.2	)		(0.5	)
Effective income tax rate		3.2	%		30.1	%		24.3	%

Schedule of provision for income taxes

The components of the provision for income taxes are as follows (in thousands):

	Year ended April 30,
	2013			2012			2011
Current:
Federal	$	(3,818	)	$	12,814		$	8,660
State		334			1,651			641
		(3,484	)		14,465			9,301
Deferred:
Federal		5,178			(187	)		859
State		(1,347	)		(1,134	)		(1,836	)
		3,831			(1,321	)		(977	)
Change in valuation allowance		—			(57	)		(5	)
Total income tax expense	$	347		$	13,087		$	8,319

Schedule of components of the Company's deferred income tax assets and liabilities

Significant components of the Company's deferred income tax assets and liabilities are as follows (in thousands):

	April 30,
	2013			2012
Deferred income tax assets:
Accrued expenses	$	6,266		$	9,697
Allowances, reserves, and other		3,050			763
Capital loss and credit carry-forwards		4,908			4,508
Unrealized loss on securities		—			454
Total deferred income tax assets		14,224			15,422
Deferred income tax liabilities:
Unrealized gain on securities		(1,811	)		—
Tax over book depreciation		(1,641	)		(836	)
Total deferred income tax liabilities		(3,452	)		(836	)
Net deferred tax assets	$	10,772		$	14,586

Summary of activity related to gross unrecognized tax benefits

The following table summarizes the activity related to our gross unrecognized tax benefits for the years ended April 30, 2013 and 2012 (in thousands):

	April 30,
	2013			2012
Balance as of May 1	$	4,507		$	4,655
Increases related to prior year tax positions		539			—
Decreases related to prior year tax positions		(19	)		(533	)
Increases related to current year tax positions		1,141			973
Decreases related to lapsing of statute of limitations		(1,085	)		(588	)
Balance as of April 30	$	5,083		$	4,507