Balance Sheet Components (in thousands)

Available-for-sale short-term investments



	As of
	September 28, 2014								December 31, 2013
	Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value		Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
U.S. treasuries	$	99,954	$	31	$	—	$	99,985	$	104,595	$	7	$	(1	)	$	104,601
Certificates of deposits	166		—		—		166		159		—		—			159
Total	$	100,120	$	31	$	—	$	100,151	$	104,754	$	7	$	(1	)	$	104,760

The Company’s short-term investments are primarily comprised of marketable securities that are classified as available-for-sale and consist of government securities with an original maturity or remaining maturity at the time of purchase of greater than three months and no more than 12 months. Accordingly, none of the available-for-sale securities have unrealized losses greater than 12 months.

Cost method investments

As of September 28, 2014 and December 31, 2013, the carrying value of the Company's cost method investments was $1.3 million. These investments are included in other non-current assets in the unaudited condensed consolidated balance sheets and are carried at cost, adjusted for any impairment, because the Company does not have a controlling interest and does not have the ability to exercise significant influence over these companies. The Company monitors these investments for impairment on a quarterly basis, and adjusts carrying value for any impairment charges recognized. There were no impairments recognized in the three and nine months ended September 28, 2014 and September 29, 2013. Realized gains and losses on these investments are reported in other income, net in the unaudited condensed consolidated statements of operations.

Accounts receivable, net



	As of
	September 28, 2014			December 31, 2013
Gross accounts receivable	$	299,216		$	289,479
Allowance for doubtful accounts	(1,255		)	(1,255		)
Allowance for sales returns	(16,867		)	(17,467		)
Allowance for price protection	(2,526		)	(4,273		)
Total allowances	(20,648		)	(22,995		)
Total accounts receivable, net	$	278,568		$	266,484

Inventories



	As of
	September 28, 2014		December 31, 2013
Raw materials	$	3,833	$	8,676
Work in process	—		6,233
Finished goods	202,661		209,547
Total inventories	$	206,494	$	224,456

The Company records provisions for excess and obsolete inventory based on forecasts of future demand. While management believes the estimates and assumptions underlying its current forecasts are reasonable, there is risk that additional charges may be necessary if current forecasts are greater than actual demand.

Property and equipment, net



	As of
	September 28, 2014			December 31, 2013
Computer equipment	$	9,334		$	8,527
Furniture, fixtures and leasehold improvements	17,670			14,019
Software	28,318			25,722
Machinery and equipment	57,038			50,656
Construction in progress	5			21
Total property and equipment, gross	112,365			98,945
Accumulated depreciation and amortization	(84,736		)	(71,751		)
Total property and equipment, net	$	27,629		$	27,194

Depreciation and amortization expense pertaining to property and equipment was $4.6 million and $13.1 million for the three and nine months ended September 28, 2014, respectively, and $4.9 million and $12.7 million for the three and nine months ended September 29, 2013, respectively.

Intangibles, net



	Gross		Accumulated Amortization			Net
September 28, 2014
Technology	$	61,099	$	(36,901	)	$	24,198
Customer contracts and relationships	56,500		(14,434		)	42,066
Other	10,545		(6,104		)	4,441
Total intangibles, net	$	128,144	$	(57,439	)	$	70,705



	Gross		Accumulated Amortization			Net
December 31, 2013
Technology	$	60,999	$	(29,593	)	$	31,406
Customer contracts and relationships	56,500		(9,120		)	47,380
Other	10,545		(5,313		)	5,232
Finite-lived intangibles, net	128,044		(44,026		)	84,018
Indefinite-lived intangible assets	100		—			100
Total intangibles, net	$	128,144	$	(44,026	)	$	84,118

Amortization of purchased intangible assets was $4.5 million and $13.4 million for the three and nine months ended September 28, 2014, respectively, and $4.5 million and $11.0 million for the three and nine months ended September 29, 2013, respectively.

Estimated amortization expense related to intangibles for each of the next five years and thereafter is as follows:



Year Ending December 31	Amount
2014 (remaining three months)	$	4,475
2015	17,283
2016	16,921
2017	11,386
2018	7,871
Thereafter	12,769
Total expected amortization expense	$	70,705

Goodwill

The changes in the carrying amount of goodwill during the nine months ended September 28, 2014 are as follows:



	Retail		Commercial		Service Provider		Total
Goodwill at December 31, 2013	$	45,441	$	36,279	$	74,196	$	155,916
Goodwill acquired during the period	—		—		—		—
Goodwill at September 28, 2014	$	45,441	$	36,279	$	74,196	$	155,916

There were no impairments to goodwill during the three and nine months ended September 28, 2014 and September 29, 2013.

Other non-current assets



	As of
	September 28, 2014		December 31, 2013
Non-current deferred income taxes	$	21,713	$	20,235
Cost method investment	1,322		1,322
Other	8,364		5,034
Total other non-current assets	$	31,399	$	26,591

Other accrued liabilities



	As of
	September 28, 2014		December 31, 2013
Sales and marketing programs	$	46,420	$	47,941
Warranty obligation	42,752		48,754
Freight	6,873		5,790
Other	37,614		40,733
Total other accrued liabilities	$	133,659	$	143,218