3. FAIR VALUE MEASUREMENTS

The Company has certain financial assets that are recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy as described in the accounting standards for fair value measurements.

Level 1 — quoted prices for identical instruments in active markets;

Level 2 — quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets; and

Level 3 — valuations derived from valuation techniques in which one or more significant value drivers are unobservable.

The tables below present information about the Company’s financial assets that are measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques it utilizes to determine such fair value:

	Fair Value Measurement as of September 30, 2015
	Total		Level 1		Level 2		Level 3
	(in thousands)
Money market funds	$	140	$	140	$	—	$	—
Commercial paper		11,099		—		11,099		—
Government and government agency bonds		28,249		—		28,249		—
Corporate bonds		15,841		—		15,841		—
Certificates of deposit		11,343		11,343		—		—
Total assets	$	66,672	$	11,483	$	55,189	$	—

	Fair Value Measurement as of December 31, 2014
	Total		Level 1		Level 2		Level 3
	(in thousands)
Money market funds	$	47,740	$	47,740	$	—	$	—
Commercial paper		2,997		—		2,997		—
Government and government agency bonds		75,250		—		75,250		—
Corporate bonds		58,546		—		58,546		—
Certificates of deposit		647		647		—		—
Total assets	$	185,180	$	48,387	$	136,793	$	—

The Company’s assets with fair value categorized as Level 1 within the fair value hierarchy include money market funds and certificates of deposit. Money market funds are publicly traded mutual funds and are presented as cash equivalents on the unaudited condensed consolidated balance sheets as of September 30, 2015.

The Company’s assets with fair value categorized as Level 2 within the fair value hierarchy consist of commercial paper, government and government agency bonds and corporate bonds. These assets have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, through income-based approaches utilizing observable market data.

The carrying amounts reported in the unaudited condensed consolidated balance sheets for cash and cash equivalents, accounts receivable and accounts payable approximate fair value because of the immediate or short-term maturity of these financial instruments. The carrying amounts for long-term debt and notes payable approximate fair value based on market activity for other debt instruments with similar characteristics and comparable risk.