Balance Sheet Account Detail

(a) Property and Equipment

Property and equipment consisted of the following:



	March 31, 2017			December 31, 2016
Production equipment, molds, and office furniture	$	11,853		$	11,714
Computer hardware and software	8,321			8,162
Leasehold improvements	15,494			15,495
Construction in progress (software and related implementation, production equipment, and leasehold improvements)	922			839
Property and equipment, at cost	$	36,590		$	36,210
Accumulated depreciation	(14,315		)	(12,945		)
Property and equipment, net	$	22,275		$	23,265

Depreciation expense for property and equipment for the three months ended March 31, 2017 and 2016 was $1.4 million and $1.3 million, respectively.

(b) Inventories

Inventories consisted of the following:



	March 31, 2017		December 31, 2016
Raw materials	$	12,127	$	13,133
Work-in-process	11,844		10,139
Finished goods	18,723		17,888
Total Inventories	$	42,694	$	41,160

The following table presents goodwill, indefinite lived intangible assets, finite lived intangible assets and related accumulated amortization:



	March 31, 2017			December 31, 2016
Goodwill	$	120,736		$	120,711

Intangible assets:
Indefinite lived intangibles
Trademarks and trade names	$	2,708		$	2,708
In-process research and development	11,200			11,200

Finite lived intangibles
Developed technology	$	67,600		$	67,600
Accumulated amortization	(4,573		)	(3,810		)
Developed technology, net	$	63,027		$	63,790

Customer relationships	$	7,500		$	7,500
Accumulated amortization	(875		)	(687		)
Customer relationships, net	$	6,625		$	6,813

Intangible assets (excluding goodwill), net	$	83,560		$	84,511

The change in the carrying amount of goodwill for the three months ended March 31, 2017 is as follows (in thousands):



Balance at January 1, 2017	120,711
Foreign currency translation adjustment	25
Balance at March 31, 2017	$	120,736

Amortization expense for intangible assets for the three months ended March 31, 2017 and 2016 was $0.9 million and $1.0 million, respectively.

Estimated amortization expense for the five succeeding years and thereafter is as follows:



Remainder of 2017	$	2,852
2018	4,575
2019	6,037
2020	7,678
2021	8,920
2022 & Thereafter	39,590
Total	$	69,652

(d) Marketable securities

Investments in held-to-maturity marketable securities consist of the following at March 31, 2017 and December 31, 2016:



	March 31, 2017
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
Agency bonds	$	3,992	$	—	$	(2	)	$	3,990
Corporate bonds	10,506		—		(10		)	10,496
Commercial paper	3,998		—		—			3,998
Total	$	18,496	$	—	$	(12	)	$	18,484

	December 31, 2016
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
Agency bonds	$	6,488	$	2	$	—		$	6,490
Corporate bonds	10,513		—		(21		)	10,492
Commercial paper	3,987		—		—			3,987
Total	$	20,988	$	2	$	(21	)	$	20,969

At March 31, 2017, the Company’s investments included 6 held-to-maturity debt securities in unrealized loss positions with a total unrealized loss of approximately $12 thousand and a total fair market value of approximately $14.5 million. All investments with gross unrealized losses have been in unrealized loss positions for less than 8 months. The unrealized losses were caused by interest rate fluctuations. There was no change in the credit risk of the securities. The Company does not intend to sell the securities and it is not likely that the Company will be required to sell the securities before the expected recovery of their amortized cost bases. There were no realized gains or losses on the investments for the three months ended March 31, 2017. All of the Company's investments of held-to-maturity securities will mature within less than 12 months with an average maturity of 2 months.

(e) Fair Value Measurements

The following fair value hierarchy table presents information about each major category of the Company’s assets and liabilities measured at fair value on a recurring basis as of March 31, 2017 and December 31, 2016:



	Fair value measurement at reporting date using:
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)		Total
At March 31, 2017
Cash and cash equivalents	$	15,541	$	—	$	—	$	15,541
Restricted cash	$	2,001	$	—	$	—	$	2,001
Contingently issuable common stock	$	—	$	—	$	13,400	$	13,400
At December 31, 2016
Cash and cash equivalents	$	26,120	$	—	$	—	$	26,120
Restricted cash	$	2,001	$	—	$	—	$	2,001
Contingently issuable common stock	$	—	$	—	$	12,200	$	12,200

There were no re-measurements to fair value during the three months ended March 31, 2017 of financial assets and liabilities that are not measured at fair value on a recurring basis. There were no transfers between Level 1, Level 2 or Level 3 securities during the three months ended March 31, 2017.

(f) Financial Instruments Not Recorded at Fair Value on a Recurring Basis

We measure the fair value of our Senior Notes carried at amortized cost quarterly for disclosure purposes. The estimated fair value of the Senior Notes is determined by Level 2 inputs and is based primarily on quoted market prices for the same or similar securities. Based on the market prices, the fair value of our long-term debt was $204.0 million as of March 31, 2017 and $187.6 million as of December 31, 2016.

We measure the fair value of our held-to-maturity marketable securities carried at amortized cost quarterly for disclosure purposes. The fair value of marketable securities is determined by Level 2 inputs and is based primarily on quoted market prices for the same or similar instruments.