Summary of Significant Accounting Policies - Additional Information (Detail)		12 Months Ended
	Apr. 01, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) PerformanceObligation Customer $ / shares shares	Mar. 31, 2018 USD ($) Customer $ / shares shares	Mar. 31, 2017 USD ($) Customer $ / shares shares
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of shares of common stock repurchased | shares		582,159	249,245	745,575
Treasury stock, value, acquired, cost method		$ 35,167,000	$ 11,187,000	$ 27,999,000
Average price per share of common stock | $ / shares		$ 60.41	$ 44.88	$ 37.56
Maturities of short term investment interest-bearing securities		90 days
Accounts receivable due period		30 days
Revenue recognition, number of performance obligation | PerformanceObligation		1
Unbilled account receivables		$ 18,434,000	$ 15,131,000
Capitalized software development costs		27,552,000	27,679,000
Accumulated amortization of software development costs		99,045,000	88,567,000
Impairment of goodwill, intangible assets or other long-lived assets		0
Goodwill		36,814,000	36,814,000
Accumulated amortization of goodwill		$ 2,069,000	$ 2,069,000
Computer Software Property and Equipment [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Amortization period of computer software		5 years
Customer Concentration Risk [Member] | Sales Revenue, Net [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Maximum customer risk percentage		10.00%	10.00%	10.00%
Number of customer | Customer		0	0	0
Credit Concentration Risk [Member] | Accounts Receivable [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Maximum customer risk percentage		10.00%	10.00%
Number of customer | Customer		0	0
Private Equity Funds [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Investment		$ 2,250,000
Reduction to investments		200,000
Fair Value, Inputs, Level 2 [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Transfer of assets		0
Transfer of liabilities		0
Fair Value, Inputs, Level 3 [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Transfer of assets		0
Transfer of liabilities		$ 0
Subsequent Event [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of shares of common stock repurchased | shares	91,925
Treasury stock, value, acquired, cost method	$ 6,400,000
Average price per share of common stock | $ / shares	$ 69.92
Subsequent Event [Member] | ASU 2016-02 [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Operating lease liabilities	$ 98,000,000