4.	Balance Sheet Components

Cash and Cash Equivalents

Cash and cash equivalents consisted of the following (in thousands):

	June 30, 2016		December 31, 2015
Cash	$	77,094	$	75,685
Money market funds		113,317		77,639
Total cash and cash equivalents	$	190,411	$	153,324

At June 30, 2016, a total of $25.6 million of our cash and cash equivalents were held outside of the U.S. in our foreign subsidiaries to be used primarily for our China operations.

Investments

All investments are classified as available-for-sale. The amortized cost, gross unrealized holding gains or losses, and fair value of the Company’s available-for-sale investments by major investments type are summarized in the tables below (in thousands):

	June 30, 2016
	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Corporate bonds	$	125,130	$	856	$	(5	)	$	125,981
Bond and mutual funds		25,371		56		—			25,427
Equity investments		125		112		—			237
Total investments	$	150,626	$	1,024	$	(5	)	$	151,645

	December 31, 2015
	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Corporate bonds	$	126,522	$	54	$	(473	)	$	126,103
Certificate of deposits		8,217		—		(2	)		8,215
Bond and mutual funds		25,052		—		—			25,052
Equity investments		126		71		—			197
Total investments	$	159,917	$	125	$	(475	)	$	159,567

At June 30, 2016, all of the available-for-sale investments had contractual maturities within three years. The Company periodically reviews its available-for-sale investments for other-than-temporary impairment. The Company considers factors such as the duration, severity and the reason for the decline in value, the potential recovery period and our intent to sell. For debt securities, the Company also considers whether (i) it is more likely than not that the Company will be required to sell the debt securities before recovery of their amortized cost basis, and (ii) the amortized cost basis cannot be recovered as a result of credit losses. During the three and six months ended June 30, 2016 and 2015, the Company did not recognize any other-than-temporary impairment loss.

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):

	June 30, 2016		December 31, 2015
Preclinical and clinical trial accruals	$	32,054	$	27,973
Payroll and related accruals		10,285		13,535
Professional services		1,041		1,662
Other		4,562		4,762
Total accrued liabilities	$	47,942	$	47,932