Consolidated Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from Operating Activities
NET INCOME	$ 16,079,000	$ 15,293,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,987,000	5,947,000
Loss on disposal of assets	116,000	111,000
Stock compensation expense	1,329,000	1,264,000
Write-off of uncollectible accounts	1,305,000	1,087,000
Changes in operating assets and liabilities
Accounts receivable	(3,167,000)	(1,459,000)
Customer deposits	433,000	(609,000)
Prepaid taxes and expenses	(191,000)	2,844,000
Other assets	0	19,000
Accounts and taxes payable	3,366,000	(974,000)
Accrued liabilities	(9,923,000)	1,163,000
Deferred income tax	(461,000)	(810,000)
Net cash provided by operating activities	15,873,000	23,876,000
Cash Flows from Investing Activities
Purchase of property and equipment	(11,658,000)	(9,032,000)
Net cash (used in) investing activities	(11,658,000)	(9,032,000)
Cash Flows from Financing Activities
Purchase of treasury stock	(10,005,000)	(11,778,000)
Tax effect of stock option exercises	973,000	1,027,000
Exercise of common stock options	525,000	1,952,000
Exercise of employee stock purchase options	157,000	160,000
Net cash (used in) financing activities	(8,350,000)	(8,639,000)
Increase in cash and cash equivalents	(4,135,000)	6,205,000
Cash and cash equivalents at beginning of period	12,269,000	10,242,000
Cash and cash equivalents at end of period	8,134,000	16,447,000
Supplemental Cash Flow Information:
Income taxes paid	7,288,000	6,165,000
Purchase of software license under finance agreement	$ 861,000	$ 1,700,000