Financial Statement Components

Accounts receivable, net consisted of the following (in thousands):



	December 31,
	2017			2016
Trade accounts receivable	$	17,481		$	12,640
Unbilled trade accounts receivable, net of advance client deposits	1,600			1,253
Allowance for doubtful accounts	(33		)	(12		)
Accounts receivable, net	$	19,048		$	13,881

Prepaid expenses and other current assets consisted of the following (in thousands):



	December 31,
	2017		2016
Prepaid expenses	$	2,437	$	2,199
Other current assets	2,403		809
Prepaid expenses and other current assets	$	4,840	$	3,008

Property and equipment, net consisted of the following (in thousands):



	December 31,
	2017			2016
Computer and network equipment	$	47,195		$	37,664
Computer software	6,974			5,133
Internal-use software development costs	500			475
Furniture and fixtures	1,282			1,130
Leasehold improvements	801			624
Property and equipment	56,752			45,026
Accumulated depreciation and amortization	(36,864		)	(30,338		)
Property and equipment, net	$	19,888		$	14,688

In accordance with our property and equipment policy, we review the estimated useful lives of our fixed assets on an ongoing basis. A review of our existing estimates indicated that the actual lives of certain data center assets were longer than previously estimated useful lives used for depreciation purposes in our financial statements. As a result, effective July 1, 2017, we changed the estimated useful lives of certain data center assets to better reflect the estimated periods during which these assets will remain in service. The estimated useful lives of these assets, which we previously depreciated for three years, have now been increased to a range of three to five years. For the year ended December 31, 2017, this change in accounting estimate decreased depreciation expense by $1.6 million and decreased both basic and diluted net loss per share by $0.03.

Depreciation and amortization expense associated with property and equipment was $7.8 million, $7.9 million, and $6.9 million for the years ended December 31, 2017, 2016 and 2015, respectively.

Property and equipment capitalized under capital lease obligations consist primarily of computer and network equipment and were as follows (in thousands):



	December 31,
	2017			2016
Gross	$	46,624		$	35,504
Less: accumulated depreciation and amortization	(30,438		)	(23,128		)
Total	$	16,186		$	12,376

Accrued and other current liabilities consisted of the following (in thousands):



	December 31,
	2017		2016
Accrued expenses	$	3,130	$	2,148
Accrued compensation and benefits	8,657		7,456
Accrued and other current liabilities	$	11,787	$	9,604