Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2015

Summary of Cash Equivalents, Marketable Securities and Long-Term Investments Measured at Fair Value

Cash equivalents, marketable securities and long-term investments measured at fair value are classified in the table below in one of the three categories described above (in thousands):

	Fair Value Measurements
December 31, 2015	Level 1		Level 2		Level 3		Total
Certificates of deposit	$	15,239	$	—	$	—	$	15,239
U.S. treasuries		7,019		—		—		7,019
Corporate bonds		—		1,000		—		1,000
Auction rate securities		—		—		2,052		2,052
	$	22,258	$	1,000	$	2,052	$	25,310

	Fair Value Measurements
December 31, 2014	Level 1		Level 2		Level 3		Total
Certificates of deposit	$	8,674	$	—	$	—	$	8,674
Money market funds		169		—		—		169
U.S. treasuries		5,557		—		—		5,557
Corporate bonds		—		2,020		—		2,020
Government-sponsored enterprise securities		—		7,493		—		7,493
Auction rate securities		—		—		1,971		1,971
	$	14,400	$	9,513	$	1,971	$	25,884

Summary of Activity for Assets Measured at Fair Value Using Significant Unobservable Inputs

Activity for assets measured at fair value using significant unobservable inputs (Level 3) is presented in the table below (in thousands):

Balance at December 31, 2014	$	1,971
Total net realized gains included in earnings		—
Total net unrealized gains included in other comprehensive income		81
Net transfers in and/out of Level 3		—
Balance at December 31, 2015	$	2,052
Amount of total losses for the period included in net loss attributable to the change in unrealized gains or losses relating to assets still held at December 31, 2015	$	—