Acquisitions - Additional Information (Detail) $ in Thousands, £ in Millions, $ in Millions										1 Months Ended		3 Months Ended			12 Months Ended
	Oct. 31, 2019 USD ($)	Oct. 31, 2019 GBP (£)	Nov. 01, 2018 USD ($)	Nov. 01, 2018 GBP (£)	Oct. 18, 2018	Jul. 09, 2018 USD ($)	Jul. 09, 2018 AUD ($)	May 31, 2017 USD ($)	Apr. 24, 2017	Jul. 31, 2019 USD ($)	Jul. 31, 2019 AUD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2019 GBP (£)	Mar. 31, 2019 AUD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Proceeds from issuance of long-term debt															$ 29,000	$ 58,000	$ 8,000
Payment of deferred purchase price first installment															3,133	78,395	9,075
Goodwill, net															311,247	302,517	269,265
Americas [Member]
Business Acquisition [Line Items]
Goodwill, net															$ 259,953	$ 255,436	$ 258,496
Symphony [Member]
Business Acquisition [Line Items]
Date of Acquisition agreement					Oct. 18, 2018
Purchase price			$ 67,600	£ 52.5								$ 67,500	£ 52.4
Payments to acquire businesses, gross			$ 57,600	£ 44.6
Effective date of acquisition			Nov. 01, 2018	Nov. 01, 2018
Deferred purchase price			$ 10,000	£ 7.9
Payment of deferred purchase price first installment	$ 3,300	£ 2.7
Business combination consideration transferred liabilities incurred payment terms															equal installments over three years, on or around November 1, 2019, 2020 and 2021
Earnout period			3 years	3 years
Earnout payable in RSUs | £				£ 3.0
Property and equipment acquired			$ 2,200
Goodwill, net			38,800
Symphony [Member] | Customer Relationships and Trade Names [Member]
Business Acquisition [Line Items]
Business combination intangible assets, primarily indefinite-lived domain names acquired			26,100
Symphony [Member] | Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Proceeds from issuance of long-term debt			$ 31,000
WhistleOut [Member]
Business Acquisition [Line Items]
Purchase price						$ 22,400	$ 30.2					$ 22,500		$ 30.3
Effective date of acquisition						Jul. 09, 2018	Jul. 09, 2018
Business combination consideration transferred liabilities incurred payment terms															three installments on or about July 1, 2019, 2020 and 2021
Earnout period						3 years	3 years
Business combination intangible assets, primarily indefinite-lived domain names acquired						$ 16,500
Property and equipment acquired						2,400
Earnout							$ 14.0
Earnout first installment										$ 4,200	$ 6.0
Goodwill, net						3,300
WhistleOut [Member] | Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Proceeds from issuance of long-term debt						$ 22,000
Global 2000 Telecommunications Services Provider [Member] | Americas [Member]
Business Acquisition [Line Items]
Date of Acquisition agreement									Apr. 24, 2017
Payments to acquire businesses, gross								$ 7,500
Effective date of acquisition								May 31, 2017
Property and equipment acquired								$ 6,000
Global 2000 Telecommunications Services Provider [Member] | Customer Relationships [Member] | Americas [Member]
Business Acquisition [Line Items]
Intangibles acquired								$ 1,500