5. Cash, Cash Equivalents and Investments

As of December 31, 2016 and 2015, the Company had invested its excess cash balances primarily in money market funds, and a corporate equity security. The Company’s securities are classified as available-for-sale and are carried at estimated fair value, with unrealized gains and losses reported in “Accumulated other comprehensive income” in stockholders’ equity, net of estimated taxes. See Note 3 for fair value measurement information. The cost of securities sold is based on the specific identification method. To date, the Company has not experienced credit losses on investments in these instruments, and it does not require collateral for its investment activities.

The following tables summarize the Company’s cash and available-for-sale securities’ amortized cost, gross unrealized

gains, gross unrealized losses, and fair value by significant investment category reported as cash and cash equivalents,

or short-term investments as of December 31, 2016 and 2015:



Summary of Cash and Available-For-Sale Securities	Adjusted Cost		Unrealized Gains		Fair Value		Cash and Cash Equivalents		Short-Term Investments
(In thousands)
December 31, 2016
Cash	$	147,150	$	—	$	147,150	$	147,150	$	—
Money market funds	4		—		4		4		—
Commercial paper	19,987		—		19,987		—		19,987
Total	$	167,141	$	—	$	167,141	$	147,154	$	19,987

December 31, 2015
Cash	$	124,082	$	—	$	124,082	$	124,082	$	—
Money market funds	94,801		—		94,801		94,801		—
Corporate securities	799		670		1,469		—		1,469
Total	$	219,682	$	670	$	220,352	$	218,883	$	1,469

We recognized approximately $882,000 and $997,000, respectively, of gains on sales of available-for-sale securities in the years ended December 31, 2016 and 2015.

The unrealized gain on investments included in “Other comprehensive income (loss), net of tax,” was approximately zero and $435,000 as of December 31, 2016 and 2015, respectively.