Property and Equipment, Net

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

Property and equipment consisted of the following as of December 31:



	2015			2014
	(in thousands)
Computer software	$	13,883		$	14,688
Telecommunications, network and computing equipment	22,829			16,459
Leasehold improvements	9,832			6,687
Furniture, fixtures and office equipment	4,229			3,569
Cost of assets placed in service	50,773			41,403
Less accumulated depreciation and amortization	(24,202		)	(18,373		)
Net book value of assets placed in service	26,571			23,030
Assets not yet placed in service	3,914			1,174
Property and equipment, net	$	30,485		$	24,204

Depreciation expense on property and equipment for the years ended December 2015, 2014, and 2013 was $9.6 million, $7.4 million, and $4.9 million, respectively.

Included in assets not yet placed in service as of December 31, 2015 are costs of approximately $1.7 million related to the development of interal-use software and new business systems. As we began capitalizing costs for the development of internal-use software and new business systems during the current fiscal year, there were no costs included in assets not yet placed in service related to the development of internal-use software and new business systems as of December 31, 2014.