Fixed Assets - Schedule of Fixed Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Owned Assets:
Owned Assets, Gross	$ 143,517	$ 127,433
Less: Accumulated depreciation and amortization	(96,079)	(82,947)
Owned Assets, net	47,438	44,486
Assets under capital leases:
Capital leased assets, gross	1,819	2,028
Less: Accumulated depreciation and amortization	(1,266)	(1,145)
Assets under capital leases, net	553	883
Fixed assets, net	47,991	45,369
Network equipment, computers and software
Owned Assets:
Owned Assets, Gross	95,245	83,140
Leasehold improvements
Owned Assets:
Owned Assets, Gross	28,603	26,416
Assets under capital leases:
Capital leased assets, gross	877	961
Office furniture and equipment
Owned Assets:
Owned Assets, Gross	14,000	12,218
Assets under capital leases:
Capital leased assets, gross	136	219
Buildings
Owned Assets:
Owned Assets, Gross	1,202	1,262
Capital work in progress
Owned Assets:
Owned Assets, Gross	3,140	3,029
Land
Owned Assets:
Owned Assets, Gross	787	826
Motor vehicles
Owned Assets:
Owned Assets, Gross	540	542
Assets under capital leases:
Capital leased assets, gross	$ 806	$ 848

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

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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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