Balance Sheet Account Detail

(a) Property and Equipment

Property and equipment consisted of the following:



	September 30, 2018			December 31, 2017
Production equipment, molds, and office furniture	$	12,051		$	12,118
Computer hardware and software	8,270			8,115
Leasehold improvements	15,535			15,499
Construction in progress (software and related implementation, production equipment, and leasehold improvements)	1,063			743
Property and equipment, at cost	$	36,919		$	36,475
Accumulated depreciation	(20,024		)	(17,263		)
Property and equipment, net	$	16,895		$	19,212

Depreciation expense for property and equipment for the three months ended September 30, 2018 and 2017 was $0.9 million and $1.2 million, respectively. For the nine months ended September 30, 2018 and 2017, depreciation expense for property and equipment was $2.8 million and $3.9 million, respectively.

(b) Inventories

Inventories consisted of the following:



	September 30, 2018		December 31, 2017
Raw materials	$	9,886	$	12,226
Work-in-process	5,991		7,736
Finished goods	26,377		25,191
Total Inventories	$	42,254	$	45,153

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



	September 30, 2018			December 31, 2017
Goodwill	$	120,872		$	120,927

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	(9,696		)	(7,167		)
Developed technology, net	$	57,904		$	60,433

Customer relationships	$	7,500		$	7,500
Accumulated amortization	(2,000		)	(1,438		)
Customer relationships, net	$	5,500		$	6,062

Intangible assets (excluding goodwill), net	$	77,312		$	80,403

The change in the carrying amount of goodwill for the nine months ended September 30, 2018 is as follows (in thousands):



Balance at December 31, 2017	120,927
Foreign currency translation adjustment	(55		)
Balance at September 30, 2018	$	120,872

Amortization expense for intangible assets for the three months ended September 30, 2018 and 2017 was $1.1 million and $1.1 million, respectively. For the nine months ended September 30, 2018 and 2017, amortization expense for intangible assets was $3.1 million and $3.0 million, respectively.

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



Remainder of 2018	$	1,030
2019	4,032
2020	4,041
2021	4,577
2022	5,701
2023 & Thereafter	44,023
Total	$	63,404

(d) 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 September 30, 2018 and December 31, 2017:



	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 September 30, 2018
Cash and cash equivalents	$	38,271	$	—	$	—	$	38,271
Restricted cash	$	4,143	$	—	$	—	$	4,143
Contingently issuable common stock	$	—	$	—	$	5,000	$	5,000
Derivative liabilities	$	—	$	—	$	8,216	$	8,216
At December 31, 2017
Cash and cash equivalents	$	57,991	$	—	$	—	$	57,991
Restricted cash	$	2,608	$	—	$	—	$	2,608
Contingently issuable common stock	$	—	$	—	$	9,300	$	9,300

There were no re-measurements to fair value during the nine months ended September 30, 2018 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 nine months ended September 30, 2018.

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

The Company measures the fair value of its 2.25% Convertible Senior Notes due 2018 (the “2.25% Senior Notes”) and 3.25% Convertible Senior Notes due 2020 (the “3.25% Senior Notes”) carried at amortized cost quarterly for disclosure purposes. The estimated fair value of the 2.25% Senior Notes and the 3.25% Senior Notes (collectively, 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 the Senior Notes was $77.1 million as of September 30, 2018 and $131.2 million as of December 31, 2017.

Due to short-term nature, the Company believes that the carrying value of its revolving line of credit approximated its fair value at September 30, 2018.

The Company measures the fair value of its Term Loan with affiliates of Deerfield Management Company, L.P. (collectively, “Deerfield”) (see Note 6 of the Notes to the Condensed Consolidated Financial Statements) carried at amortized cost quarterly for disclosure purposes. The estimated fair value of the Term Loan is determined by Level 3 inputs and is based primarily on unobservable inputs that are not corroborated by market data. The fair value of the Company’s Term Loan was $147.3 million as of September 30, 2018 and $101.9 million as of December 31, 2017.