Property and equipment, net
 12 Months Ended
Dec. 31, 2015
Property, Plant and Equipment [Abstract]  
Property and equipment
Property and Equipment
Property and equipment consisted of the following (in thousands):
 
As of December 31,
 
2015
 
2014
Leasehold improvements
$
2,046

 
$
1,058

Computer equipment
4,345

 
3,247

Software
885

 
874

Capitalization of internal-use software
2,925

 
291

Furniture and equipment
853

 
301

Total
11,054

 
5,771

Accumulated depreciation
(4,158
)
 
(2,141
)
Property and equipment, net
$
6,896

 
$
3,630


Depreciation and amortization expense for the years ended December 31, 2015, 2014 and 2013 was $2.0 million, $1.4 million and $0.6 million, respectively. Depreciation is recorded on a straight-line basis.