4.	Balance Sheet Components

Cash and Cash Equivalents

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

	March 31, 2017		December 31, 2016
Cash	$	86,679	$	79,239
Money market funds		83,919		94,543
Total cash and cash equivalents	$	170,598	$	173,782

At March 31, 2017 and December 31, 2016, a total of $24.4 million and $24.3 million, respectively, 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):

	March 31, 2017
	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Corporate bonds	$	101,898	$	147	$	(41	)	$	102,004
Certificate of deposits		1,036		—		—			1,036
Bond and mutual funds		22,704		205		(175	)		22,734
Equity investments		126		79		—			205
Total investments	$	125,764	$	431	$	(216	)	$	125,979

	December 31, 2016
	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Corporate bonds	$	126,550	$	182	$	(49	)	$	126,683
Certificate of deposits		1,037		—		—			1,037
Bond and mutual funds		22,305		157		—			22,462
Equity investments		125		100		—			225
Total investments	$	150,017	$	439	$	(49	)	$	150,407

At March 31, 2017, all of the available-for-sale investments had contractual maturities within two 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 months ended March 31, 2017, the Company did not recognize any other-than-temporary impairment loss.

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):

	March 31, 2017		December 31, 2016
Preclinical and clinical trial accruals	$	31,052	$	29,550
Payroll and related accruals		9,050		14,232
Professional services		1,434		1,252
Other		7,643		5,880
Total accrued liabilities	$	49,179	$	50,914