Schedule of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total revenue	$ 147,082	$ 149,757	$ 135,630	$ 153,903	$ 152,929	$ 162,275	$ 154,341	$ 148,404	$ 586,372	$ 617,949	$ 559,157
Cost of revenue									269,887	284,967	240,881
Operating expenses									193,478	209,071	175,776
Depreciation and amortization	2,150	2,193	2,257	2,346	2,277	1,937	1,859	1,914	8,946	7,987	8,613
Total costs and expenses	118,885	114,781	108,938	129,707	127,860	127,278	126,759	120,128	472,311	502,025	425,270
Operating income	28,197	34,976	26,692	24,196	25,069	34,997	27,582	28,276	114,061	115,924	133,887
Americas
Segment Reporting Information [Line Items]
Total revenue									465,939	489,834	445,486
Cost of revenue									202,421	218,850	183,563
Operating expenses									174,477	185,399	156,793
Depreciation and amortization									7,932	6,961	7,601
Total costs and expenses									384,830	411,210	347,957
Operating income									81,109	78,624	97,529
EMEA
Segment Reporting Information [Line Items]
Total revenue									93,582	98,273	84,744
Cost of revenue									53,661	51,938	43,080
Operating expenses									14,461	18,635	14,484
Depreciation and amortization									823	766	743
Total costs and expenses									68,945	71,339	58,307
Operating income									24,637	26,934	26,437
APAC
Segment Reporting Information [Line Items]
Total revenue									26,851	29,842	28,927
Cost of revenue									13,805	14,179	14,238
Operating expenses									4,540	5,037	4,499
Depreciation and amortization									191	260	269
Total costs and expenses									18,536	19,476	19,006
Operating income									8,315	10,366	9,921
Cloud Subscriptions
Segment Reporting Information [Line Items]
Total revenue	23,003	21,064	18,503	17,260	15,721	14,242	9,009	7,859	79,830	46,831	23,104
Cloud Subscriptions | Americas
Segment Reporting Information [Line Items]
Total revenue									69,469	40,927	20,611
Cloud Subscriptions | EMEA
Segment Reporting Information [Line Items]
Total revenue									8,465	4,762	2,075
Cloud Subscriptions | APAC
Segment Reporting Information [Line Items]
Total revenue									1,896	1,142	418
Software License
Segment Reporting Information [Line Items]
Total revenue	9,635	13,233	5,681	9,735	9,234	15,486	11,721	12,414	38,284	48,855	45,368
Cost of revenue	1,221	527	591	555	663	748	623	592	2,894	2,626	5,297
Software License | Americas
Segment Reporting Information [Line Items]
Total revenue									30,509	34,544	28,423
Software License | EMEA
Segment Reporting Information [Line Items]
Total revenue									4,308	11,518	11,406
Software License | APAC
Segment Reporting Information [Line Items]
Total revenue									3,467	2,793	5,539
Maintenance
Segment Reporting Information [Line Items]
Total revenue	38,801	37,305	35,898	35,744	38,045	37,763	37,323	36,099	147,748	149,230	147,033
Maintenance | Americas
Segment Reporting Information [Line Items]
Total revenue									116,309	118,891	117,489
Maintenance | EMEA
Segment Reporting Information [Line Items]
Total revenue									22,208	21,322	20,933
Maintenance | APAC
Segment Reporting Information [Line Items]
Total revenue									9,231	9,017	8,611
Services
Segment Reporting Information [Line Items]
Total revenue	70,915	73,470	71,778	87,406	86,308	91,626	93,951	88,631	303,569	360,516	329,685
Services | Americas
Segment Reporting Information [Line Items]
Total revenue									232,954	283,008	265,165
Services | EMEA
Segment Reporting Information [Line Items]
Total revenue									58,360	60,618	50,328
Services | APAC
Segment Reporting Information [Line Items]
Total revenue									12,255	16,890	14,192
Hardware
Segment Reporting Information [Line Items]
Total revenue	$ 4,728	$ 4,685	$ 3,770	$ 3,758	$ 3,621	$ 3,158	$ 2,337	$ 3,401	16,941	12,517	13,967
Hardware | Americas
Segment Reporting Information [Line Items]
Total revenue									16,698	12,464	13,798
Hardware | EMEA
Segment Reporting Information [Line Items]
Total revenue									241	$ 53	2
Hardware | APAC
Segment Reporting Information [Line Items]
Total revenue									$ 2		$ 167