Income Taxes (Tables)

12 Months Ended

Mar. 31, 2012

Income Taxes [Abstract]

Income Before Income Tax Expense

	Year Ended March 31,
	2012		2011		2010
Domestic	$	49,525	$	53,008	$	40,371
Foreign		1,393		3,285		2,700
	$	50,918	$	56,293	$	43,071

Components Of The Income Tax Expense

	Year Ended March 31,
	2012			2011		2010
Current income tax expense:
Federal	$	10,585		$	13,197	$	8,498
State		1,421			1,268		611
Foreign		1,032			1,104		856
		13,038			15,569		9,965
Deferred income tax expense (benefit):
Federal		5,603			2,967		4,826
State		44			492		363
Foreign		(195	)		0		0
		5,452			3,459		5,189
	$	18,490		$	19,028	$	15,154

Federal Statutory Income Tax Rate

	Year Ended March 31,
	2012			2011			2010
Statutory U.S. federal tax rate		35.0	%		35.0	%		35.0	%
State taxes, net of federal tax effect		3.2			3.0			3.1
Research and development tax credits		(2.1	)		(2.1	)		(1.7	)
Tax rate differential of foreign operations		0.1			(0.2	)		(0.2	)
Domestic production activities deduction		(2.4	)		(3.0	)		(1.7	)
Transaction costs		1.5			0			0
Other		1.0			1.1			0.7
		36.3	%		33.8	%		35.2	%

Components Of Net Deferred Tax Assets

	Year Ended March 31,
	2012			2011
Assets:
Accrued expenses	$	3,841		$	3,475
Depreciation		1,333			1,639
Deferred revenue		5,743			6,750
Reserves		892			648
Net operating loss carryforwards		22,622			20,933
Tax credit carryforwards		1,994			1,994
Share-based compensation		760			522
Auction rate securities temporary impairment		73			883
Other		264			434
		37,522			37,278
Liabilities:
Intangible assets		(13,274	)		(8,479	)
Share-based compensation		0			0
Valuation allowance		(3,529	)		(249	)
	$	20,719		$	28,550

Schedule Of Unrecognized Tax Benefits

	Year Ended March 31,
	2012			2011		2010
Balance at April 1,	$	383		$	349	$	314
Additions based on tax positions related to the current year		34			34		35
Release of tax positions of prior years		(82	)		0		0
Balance at March 31,	$	335		$	383	$	349