Balance Sheet Components (in thousands)

Short-Term Investments



	As of
	December 31, 2013									December 31, 2012
	Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value		Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
U.S. Treasuries	$	104,595	$	7	$	(1	)	$	104,601	$	225,016	$	48	$	(2	)	$	225,062
Certificates of Deposits	159		—		—			159		2,783		—		—			2,783
Mutual Funds	385		—		—			385		—		—		—			—
Total	$	105,139	$	7	$	(1	)	$	105,145	$	227,799	$	48	$	(2	)	$	227,845

The Company’s marketable securities are classified as available-for-sale consisting of government securities and trading securities consisting of mutual funds. All the securities are 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 short-term investments have unrealized losses greater than 12 months.

Cost Method Investments

As of December 31, 2013 and December 31, 2012, 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 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 years ended December 31, 2013 and December 31, 2012. Realized gains and losses on these investments are reported in other income (expense), net in the consolidated statements of operations. In the third fiscal quarter of 2012 the Company recognized a gain of $3.1 million on the partial sale of one of its cost method investments. No other gains or losses were recorded in the years ended December 31, 2013 and December 31, 2012.

Accounts receivable, net



	As of
	December 31, 2013			December 31, 2012
Gross accounts receivable	$	289,479		$	276,084
Allowance for doubtful accounts	(1,255		)	(1,256		)
Allowance for sales returns	(17,467		)	(17,031		)
Allowance for price protection	(4,273		)	(1,783		)
Total allowances	(22,995		)	(20,070		)
Total accounts receivable, net	$	266,484		$	256,014

Inventories



	As of
	December 31, 2013		December 31, 2012
Raw materials	$	8,676	$	4,447
Work-in-process	6,233		—
Finished goods	209,547		170,456
Total inventories	$	224,456	$	174,903

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
	December 31, 2013			December 31, 2012
Computer equipment	$	8,527		$	7,290
Furniture, fixtures and leasehold improvements	14,019			12,761
Software	25,722			21,521
Machinery and equipment	50,656			31,694
Construction in progress	21			385
Total property and equipment, gross	98,945			73,651
Accumulated depreciation and amortization	(71,751		)	(54,626		)
Total property and equipment, net	$	27,194		$	19,025

Depreciation and amortization expense pertaining to property and equipment was $17.3 million, $11.9 million and $9.9 million for the years ended December 31, 2013, 2012 and 2011, respectively.

Intangibles, net

The following tables present details of the Company’s purchased intangible assets:



	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 purchased intangible assets, net	$	128,144	$	(44,026	)	$	84,118



	Gross		Accumulated Amortization			Net
December 31, 2012
Technology	$	32,259	$	(22,065	)	$	10,194
Customer contracts and relationships	16,000		(3,301		)	12,699
Other	6,870		(3,142		)	3,728
Finite-lived intangibles, net	55,129		(28,508		)	26,621
Indefinite-lived intangible assets	1,000		—			1,000
Total purchased intangible assets, net	$	56,129	$	(28,508	)	$	27,621

The Company purchased finite-lived intangible assets of $64.2 million and indefinite-lived assets of $9.5 million, as a result of its acquisition of AirCard and Arada during the second quarter of 2013. For further discussion regarding the AirCard and Arada acquisitions, see Note 2, Business Acquisitions. In addition, the Company purchased $0.3 million in patents during the second quarter of 2013.

As of December 31, 2013, the Company had $0.1 million in indefinite-lived intangible assets. This balance relates to the remaining IPR&D assets acquired in connection with the Company's acquisition of AirCard. IPR&D assets represent IPR&D projects that have not reached technical feasibility and are required to be classified as indefinite-lived assets until the successful completion or abandonment of the associated research and development efforts. Accordingly, during the development period after the date of acquisition, these assets will not be amortized. When the asset reaches technical feasibility, the Company will determine the useful life of the asset, reclassify the asset out of IPR&D, and begin amortization. Development costs incurred after acquisition on acquired IPR&D projects are expensed as incurred. As of December 31, 2013, $7.4 million of the IPR&D had reached technical feasibility and as a result, was reclassified from IPR&D to technology. In addition, $2.0 million of IPR&D projects were abandoned during the third quarter of 2013. The Company expects to complete the remaining IPR&D by the second quarter of 2014, for an estimated future cost to complete of $0.2 million.

Amortization of purchased intangible assets in the years ended December 31, 2013, 2012 and 2011 was $15.5 million, $4.9 million and $4.8 million, respectively. In the year ended December 31, 2013, the Company recorded an impairment charge of $2.0 million due to the abandonment of IPR&D discussed above. No impairment charges were recorded in the years ended December 31, 2012 and 2011.

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



Year Ending December 31,	Amount
2014	$	17,875
2015	17,258
2016	16,896
2017	11,361
2018	7,859
Thereafter	12,769
Total expected amortization expense	$	84,018

Goodwill

The changes in the carrying amount of goodwill during the years ended December 31, 2013 and 2012 are as follows:



	Retail		Commercial		Service Provider		Total
Goodwill at December 31, 2011	$	33,546	$	32,043	$	20,355	$	85,944
Goodwill acquired during the period	11,895		3,041		—		14,936
Goodwill at December 31, 2012	45,441		35,084		20,355		100,880
Goodwill acquired during the period	—		1,195		53,841		55,036
Goodwill at December 31, 2013	$	45,441	$	36,279	$	74,196	$	155,916

During 2013, the Company recorded goodwill of $55.0 million, related to its acquisitions of AirCard and Arada, including an adjustment of $0.5 million to goodwill, related to a change in the estimated fair value of inventory acquired in the AirCard acquisition. Refer to Note 2, Business Acquisitions, for additional information regarding the Company's acquisitions.

There were no impairments to goodwill in the years ended December 31, 2013, 2012 and 2011. Refer to Note 1, The Company and Summary of Significant Accounting Policies, for additional information regarding the Company's goodwill impairment assessment.

Other non-current assets



	As of
	December 31, 2013		December 31, 2012
Non-current deferred income taxes	$	20,235	$	16,856
Cost method investment	1,322		1,322
Other	5,034		4,656
Total other non-current assets	$	26,591	$	22,834

Other accrued liabilities



	As of
	December 31, 2013		December 31, 2012
Sales and marketing programs	$	47,941	$	43,652
Warranty obligation	48,754		46,659
Freight	5,790		4,457
Other	40,733		31,487
Total other accrued liabilities	$	143,218	$	126,255