Property and Equipment, net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Owned Assets:
Owned assets, gross	$ 228,850	$ 207,318
Less: Accumulated depreciation and amortization	(155,798)	(141,059)
Owned assets, net	73,052	66,259
Assets under capital leases:
Assets under capital leases, gross	1,459	1,818
Less: Accumulated depreciation and amortization	(1,001)	(1,320)
Assets under capital leases, net	458	498
Property and equipment, net	73,510	66,757
Network equipment and computers
Owned Assets:
Owned assets, gross	$ 85,921	77,587
Network equipment and computers \| Minimum
Owned Assets:
Estimated useful life	3 years
Network equipment and computers \| Maximum
Owned Assets:
Estimated useful life	5 years
Software
Owned Assets:
Owned assets, gross	$ 69,752	59,325
Software \| Minimum
Owned Assets:
Estimated useful life	3 years
Software \| Maximum
Owned Assets:
Estimated useful life	5 years
Leasehold improvements
Owned Assets:
Owned assets, gross	$ 39,533	38,857
Assets under capital leases:
Assets under capital leases, gross	$ 778	941
Leasehold improvements \| Minimum
Owned Assets:
Estimated useful life	3 years
Leasehold improvements \| Maximum
Owned Assets:
Estimated useful life	8 years
Office furniture and equipment
Owned Assets:
Owned assets, gross	$ 20,097	19,667
Assets under capital leases:
Assets under capital leases, gross	$ 53	167
Office furniture and equipment \| Minimum
Owned Assets:
Estimated useful life	3 years
Office furniture and equipment \| Maximum
Owned Assets:
Estimated useful life	8 years
Motor vehicles
Owned Assets:
Owned assets, gross	$ 635	638
Assets under capital leases:
Assets under capital leases, gross	$ 628	710
Motor vehicles \| Minimum
Owned Assets:
Estimated useful life	2 years
Motor vehicles \| Maximum
Owned Assets:
Estimated useful life	5 years
Buildings
Owned Assets:
Estimated useful life	30 years
Owned assets, gross	$ 1,140	1,245
Land
Owned Assets:
Owned assets, gross	746	815
Capital work in progress
Owned Assets:
Owned assets, gross	$ 11,026	$ 9,184

Cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land or leased assets).

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