Cash, Cash Equivalents, and Available for Sale Marketable Investments (Tables)

3 Months Ended

Mar. 31, 2017

Cash and Cash Equivalents [Abstract]

Cash, cash equivalents and investments, available for sale

Cash, cash equivalents, and marketable securities included the following at March 31, 2017 and December 31, 2016:

	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
	(in thousands)
As of March 31, 2017
Money market funds included in cash and cash equivalents	$	41,973	$	—	$	—	$	41,973
Marketable securities:
U.S. Treasury notes		114,148		—		82		114,066
Total debt securities	$	114,148	$	—	$	82	$	114,066
Equity securities		1,220		780		—		2,000
Total marketable securities	$	115,368	$	780	$	82	$	116,066
Total money market funds and marketable securities	$	157,341	$	780	$	82	$	158,039
As of December 31, 2016
Money market funds included in cash and cash equivalents	$	36,003	$	—	$	—	$	36,003
Marketable securities:
U.S. Treasury notes		130,237		2		66		130,173
U.S. Government agency bonds		7,604		—		—		7,604
Total debt securities	$	137,841	$	2	$	66	$	137,777
Equity securities		1,220		140		—		1,360
Total marketable securities		139,061		142		66		139,137
Total money market funds and marketable securities	$	175,064	$	142	$	66	$	175,140

Estimated fair value of the Company’s marketable securities balance

The estimated fair value of the Company’s debt securities balance at March 31, 2017, by contractual maturity, is as follows:

Due in one year or less $ 114,066