Property and Equipment, net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Owned Assets:
Owned assets, gross	$ 247,699	$ 228,850
Less: Accumulated depreciation and amortization	(170,316)	(155,798)
Owned assets, net	77,383	73,052
Right-of-use assets under finance leases:
Finance lease, right of use asset, gross	1,888	1,459
Less: Accumulated depreciation and amortization	(1,188)	(1,001)
Property and equipment, net	700	458
Property and equipment, net	78,083	73,510
Network equipment and computers
Owned Assets:
Owned assets, gross	91,514	85,921
Software
Owned Assets:
Owned assets, gross	73,308	69,752
Leasehold improvements
Owned Assets:
Owned assets, gross	43,577	39,533
Right-of-use assets under finance leases:
Finance lease, right of use asset, gross	798	778
Office furniture and equipment
Owned Assets:
Owned assets, gross	22,034	20,097
Right-of-use assets under finance leases:
Finance lease, right of use asset, gross	348	53
Motor vehicles
Owned Assets:
Owned assets, gross	723	635
Right-of-use assets under finance leases:
Finance lease, right of use asset, gross	$ 742	628
Buildings
Owned Assets:
Estimated useful lives	30 years
Owned assets, gross	$ 1,152	1,140
Land
Owned Assets:
Owned assets, gross	754	746
Capital work in progress
Owned Assets:
Owned assets, gross	$ 14,637	$ 11,026
Minimum \| Network equipment and computers
Owned Assets:
Estimated useful lives	3 years
Minimum \| Software
Owned Assets:
Estimated useful lives	3 years
Minimum \| Leasehold improvements
Owned Assets:
Estimated useful lives	3 years
Minimum \| Office furniture and equipment
Owned Assets:
Estimated useful lives	3 years
Minimum \| Motor vehicles
Owned Assets:
Estimated useful lives	2 years
Maximum \| Network equipment and computers
Owned Assets:
Estimated useful lives	5 years
Maximum \| Software
Owned Assets:
Estimated useful lives	5 years
Maximum \| Leasehold improvements
Owned Assets:
Estimated useful lives	8 years
Maximum \| Office furniture and equipment
Owned Assets:
Estimated useful lives	8 years
Maximum \| Motor vehicles
Owned Assets:
Estimated useful lives	5 years

Finance Lease, Right-of-Use, Accumulated Depreciation

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Finance Lease, Right-of-Use Asset, Gross

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

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Amount of lessee's right to use underlying asset under finance lease.

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Gross amount of long-lived physical assets excluding assets held under lease agreements used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets excluding assets held under lease agreements used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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