CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net income	$ 2,139	$ 8,617
Adjustments to reconcile net income to net cash provided by operating activites:
Depreciation	675	505
Amortization	340	357
Stock-based compensation	907	556
Deferred income tax provision	873	5,778
Other	158	75
Changes in assets and liabilities:
Accounts receivable, net	132	(626)
Inventory	(61)	(19)
Other current and noncurrent assets	(306)	(148)
Deferred cost of goods sold	30	(14)
Accounts payable	(316)	(35)
Accrued compensation	82	(22)
Accrued warranty	22	18
Accrued taxes and fees	192	112
Deferred revenue	373	(183)
Other current and noncurrent liabilities	(7)	(45)
Net cash provided by operating activities	5,233	14,926
Cash flows from investing activities:
Purchases of property and equipment	(466)	(1,048)
Cost of capitalized software	(328)	0
Net cash used in investing activities	(794)	(1,048)
Cash flows from financing activities:
Capital lease payments	(5)	(43)
Repurchase of common stock	(120)	(74)
Proceeds from issuance of common stock under employee stock plans	1,296	87
Net cash provided by (used in) financing activities	1,171	(30)
Net increase in cash and cash equivalents	5,610	13,848
Cash and cash equivalents at the beginning of the period	50,305	22,426
Cash and cash equivalents at the end of the period	$ 55,915	$ 36,274