Revenue from Contracts with Customers - Summary of Impact of Adoption of ASC 606 on Consolidated Balance Sheet and Consolidated Statements of Net Income and Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Apr. 01, 2018	Mar. 31, 2018
ASSETS
Accounts receivable, net		$ 84,360		$ 84,360			$ 84,962
Contract assets		11,281		11,281
Income taxes receivable		6,061		6,061			8,122
Prepaid expenses and other current assets		18,505		18,505			17,180
Deferred income taxes, net		6,417		6,417			9,219
Contract assets, net of current		3,608		3,608
Other assets		29,620		29,620			18,795
LIABILITIES
Contract liabilities		50,449		50,449			54,079
Accrued compensation and related benefits		24,179		24,179			27,910
Other current liabilities		41,610		41,610			48,317
Contract liabilities, net of current							1,173
Shareholders' equity:
Retained earnings	[1]	107,693		107,693			$ 78,708
Revenues:
Total revenues		130,867	$ 131,715	394,388	$ 395,244
Total cost of revenue		61,671	61,634	184,640	179,558
Gross profit		69,196	70,081	209,748	215,686
Operating expenses:
Selling, general and administrative		41,304	43,563	120,169	127,517
Research and development costs, net		20,682	20,645	61,181	60,161
Amortization of acquired intangible assets		1,027	1,956	3,316	6,015
Total operating expenses		63,013	66,294	184,666	193,823
Income from operations		6,183	3,787	25,082	21,863
Interest and other income, net		(903)		(1,722)
Income before provision for income taxes		5,280	3,028	23,360	19,601
Provision for income taxes		456	1,487	2,794	6,134
Net income		4,824	$ 1,541	20,566	$ 13,467
Recurring
Revenues:
Total revenues		117,446		353,770
Software, Hardware, and Other Non-recurring
Revenues:
Total revenues		13,421		40,618
Adoption of ASC 606
ASSETS
Accounts receivable, net						$ 87,342
Contract assets						13,446
Prepaid expenses and other current assets						16,957
Deferred income taxes, net						6,335
Contract assets, net of current						2,731
Other assets						25,474
LIABILITIES
Contract liabilities						58,253
Accrued compensation and related benefits						28,655
Other current liabilities						58,281
Shareholders' equity:
Retained earnings						87,127
Adoption of ASC 606 | ASC 606 Transition Adjustments
ASSETS
Accounts receivable, net		1,298		1,298		2,380
Contract assets		(11,281)		(11,281)		13,446
Income taxes receivable		1,550		1,550
Prepaid expenses and other current assets		(2,935)		(2,935)		(223)
Deferred income taxes, net		2,884		2,884		(2,884)
Contract assets, net of current		(3,608)		(3,608)		2,731
Other assets		(6,808)		(6,808)		6,679
LIABILITIES
Contract liabilities		235		235		4,174
Accrued compensation and related benefits		300		300		745
Other current liabilities		(7,777)		(7,777)		9,964
Contract liabilities, net of current		910		910		(1,173)
Shareholders' equity:
Retained earnings		(12,568)		(12,568)		$ 8,419
Revenues:
Total revenues		(524)		(1,367)
Total cost of revenue		36		130
Gross profit		(560)		(1,497)
Operating expenses:
Selling, general and administrative		1,050		4,202
Total operating expenses		1,050		4,202
Income from operations		(1,610)		(5,699)
Income before provision for income taxes		(1,610)		(5,699)
Provision for income taxes		(553)		(1,550)
Net income		(1,057)		(4,149)
Adoption of ASC 606 | ASC 606 Transition Adjustments | Recurring
Revenues:
Total revenues		(557)		(663)
Adoption of ASC 606 | ASC 606 Transition Adjustments | Software, Hardware, and Other Non-recurring
Revenues:
Total revenues		33		(704)
Adoption of ASC 606 | Calculated under Revenue Guidance in Effect before Topic 606
ASSETS
Accounts receivable, net		85,658		85,658
Income taxes receivable		7,611		7,611
Prepaid expenses and other current assets		15,570		15,570
Deferred income taxes, net		9,301		9,301
Other assets		22,812		22,812
LIABILITIES
Contract liabilities		50,684		50,684
Accrued compensation and related benefits		24,479		24,479
Other current liabilities		33,833		33,833
Contract liabilities, net of current		910		910
Shareholders' equity:
Retained earnings		95,125		95,125
Revenues:
Total revenues		130,343		393,021
Total cost of revenue		61,707		184,770
Gross profit		68,636		208,251
Operating expenses:
Selling, general and administrative		42,354		124,371
Research and development costs, net		20,682		61,181
Amortization of acquired intangible assets		1,027		3,316
Total operating expenses		64,063		188,868
Income from operations		4,573		19,383
Interest and other income, net		(903)		(1,722)
Income before provision for income taxes		3,670		17,661
Provision for income taxes		(97)		1,244
Net income		3,767		16,417
Adoption of ASC 606 | Calculated under Revenue Guidance in Effect before Topic 606 | Recurring
Revenues:
Total revenues		116,889		353,107
Adoption of ASC 606 | Calculated under Revenue Guidance in Effect before Topic 606 | Software, Hardware, and Other Non-recurring
Revenues:
Total revenues		$ 13,454		$ 39,914

[1] Includes cumulative effect adjustment related to the adoption of ASC 606, as defined in Note 1. See Note 1 for additional details.