4. Property and equipment

The following is a summary of property and equipment, at cost less accumulated depreciation and amortization:

	June 30, 2015			December 31, 2014
Leasehold improvements	$	179,401		$	152,627
Construction in progress	42,814			20,104
Computer equipment	10,698			7,909
Software	20,840			17,827
Office equipment	1,739			297

Total property and equipment	255,492			198,764
Less: accumulated depreciation and amortization	(103,486		)	(86,992		)

Total property and equipment, net	$	152,006		$	111,772

Depreciation and amortization expense, which includes depreciation and amortization for property and equipment under capital leases, is allocated as follows in the accompanying condensed consolidated statements of operations:

	Three Months Ended June 30,				Six Months Ended June 30,
	2015		2014		2015		2014

Network access	$	6,155	$	4,511	$	10,987	$	8,373
Network operations	1,843		1,182		3,829		2,369
Development and technology	1,336		782		2,510		1,479
General and administrative	478		56		540		94

Total depreciation and amortization of property and equipment	$	9,812	$	6,531	$	17,866	$	12,315