Consolidated financial statement details

The following sections and tables provide details of selected balance sheet items.

Inventory



	December 31,
(in thousands)	2015		2014
Components	$	9,476	$	4,324
Finished goods	178,756		148,702
Total inventory	$	188,232	$	153,026

Prepaid expenses and other current assets



	December 31,
(in thousands)	2015		2014
Prepaid expenses	$	6,132	$	3,905
Prepaid income taxes	4,696		26,504
Tenant allowance receivable	4,249		—
Prepaid licenses	2,818		2,053
Current deferred tax assets	—		24,218
Other current assets	7,366		7,089
Prepaid expenses and other current assets	$	25,261	$	63,769

Property and equipment, net



(dollars in thousands)	Useful life (in years)	December 31, 2015			December 31, 2014
Leasehold improvements	3–10	$	40,841		$	22,787
Production, engineering and other equipment	4	25,174			8,755
Tooling	1–2	19,537			16,159
Computers and software	2	14,581			9,731
Furniture and office equipment	3	11,389			6,150
Construction in progress		4,632			3,944
Tradeshow equipment and other	2-5	4,136			3,830
Gross property and equipment		120,290			71,356
Less: Accumulated depreciation and amortization		(50,240		)	(29,800)
Property and equipment, net		$	70,050		$	41,556

Depreciation expense was $24.8 million, $16.8 million and $10.9 million in 2015, 2014 and 2013, respectively.

Acquisitions and acquired intangible assets and goodwill

In 2015, the Company completed acquisitions qualifying as business combinations for aggregate consideration of $70.2 million, the substantial majority of which was cash consideration. These acquisitions were not material to the Company's consolidated financial statements, either individually or in the aggregate, and therefore actual and proforma disclosures under the applicable accounting guidance have not been presented.

The following table summarizes the allocation of the fair values of the assets acquired and liabilities assumed, and the related useful lives, where applicable:



(in thousands)	Estimated useful life (in years)	Fair value
Purchased technology	4 - 6 years	$	25,676
In-process research and development (IPR&D)		6,600
Net liabilities assumed		(353		)
Deferred income tax liabilities		(4,676		)
Net assets acquired		27,247
Goodwill		43,000
Total fair value consideration		$	70,247

Goodwill is primarily attributable to expected synergies in the technologies that can be leveraged by the Company in future product offerings related to device and software offerings. Goodwill is not expected to be deductible for tax purposes. The carrying amount of goodwill was $57.1 million and $14.1 million as of December 31, 2015 and 2014, respectively. The increase in 2015 and 2014 was entirely attributable to goodwill acquired.

The following table summarizes the Company's acquired intangible assets:



	December 31, 2015
(in thousands)	Gross carrying value		Accumulated amortization			Net carrying value
Purchased technology and other amortizable assets	$	32,952	$	(8,540	)	$	24,412
IPR&D and other non-amortizable assets	6,615		—			6,615
Total intangible assets	$	39,567	$	(8,540	)	$	31,027



	December 31, 2014
(in thousands)	Gross carrying value		Accumulated amortization			Net carrying value
Purchased technology and other amortizable assets	$	7,275	$	(4,353	)	$	2,922
Other non-amortizable assets	15		—			15
Total intangible assets	$	7,290	$	(4,353	)	$	2,937

As of December 31, 2015, technological feasibility has not been established for IPR&D assets; they have no alternative future use and, as such, continue to be accounted for as indefinite-lived intangible assets.

Amortization expense was $4.2 million, $1.1 million and $1.1 million in 2015, 2014 and 2013, respectively. At December 31, 2015, the estimated amortization expense of existing intangible assets for future periods is as follows:



(in thousands)	Total
Year ending December 31,
2016	$	5,956
2017	5,172
2018	4,780
2019	4,269
2020	3,365
Thereafter	870
	$	24,412

Other long-term assets



	December 31,
(in thousands)	2015		2014
POP displays	$	27,989	$	18,743
Long-term deferred tax assets	41,936		8,611
Income tax receivable	33,206		—
Deposits and other	8,430		8,706
Other long-term assets	$	111,561	$	36,060

Accrued liabilities



	December 31,
(in thousands)	2015		2014
Accrued payables	$	64,831	$	56,617
Excess purchase order commitments	38,477		447
Accrued sales incentive	29,298		9,635
Employee related liabilities	26,491		28,959
Warranty liability	10,400		6,025
Customer deposits	8,877		4,903
Income taxes payable	7,536		2,732
Other	6,536		9,189
Accrued liabilities	$	192,446	$	118,507