INVESTMENTS

The Company's investments consist of long-term variable rate debt instruments with an auction reset feature, referred to as auction rate securities ("ARS"), and are classified as available-for-sale and are carried at fair value.

Scheduled maturities of investments classified as available-for-sale as of December 31, 2018 are as follows (in thousands):



Maturity	Fair Value
Due in:
2019	$	—
2020 — 2023	—
2024 — 2028	—
2029 and thereafter	10,070
Available-for-sale investments	$	10,070

The Company had no realized gains or losses on its investments during the years ended December 31, 2018, 2017 and 2016. Realized gains and losses from the sale of available-for-sale securities are determined on a specific-identification basis.

As of December 31, 2018, the amortized cost basis and fair value of investments classified as available-for-sale were as follows (in thousands):



	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Auction rate securities	$	10,800	$	—	$	(730	)	$	10,070
Available-for-sale investments	$	10,800	$	—	$	(730	)	$	10,070

As of December 31, 2017, the amortized cost basis and fair value of investments classified as available-for-sale were as follows (in thousands):



	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Auction rate securities	$	10,800	$	—	$	(730	)	$	10,070
Available-for-sale investments	$	10,800	$	—	$	(730	)	$	10,070

The unrealized losses on the Company’s investments as of December 31, 2018 and 2017 were generated primarily from changes in interest rates and ARS that failed to settle at auction, due to adverse conditions in the global credit markets. The losses are considered temporary, as the contractual terms of these investments do not permit the issuer to settle the security at a price less than the amortized cost of the investment. Because the Company does not intend to sell these instruments and it is not more likely than not that the Company will be required to sell these instruments prior to anticipated recovery, which may be at maturity, the Company does not consider these investments to be other-than-temporarily impaired as of December 31, 2018 and 2017. See Note 6 for further discussion of the fair value of the Company’s financial assets.

The components of the Company’s investments in an unrealized loss position for twelve months or longer were as follows (in thousands):



	December 31,
	2018					2017
	Aggregate Fair Value		Gross Unrealized Losses			Aggregate Fair Value		Gross Unrealized Losses
Auction rate securities	$	10,070	$	(730	)	$	10,070	$	(730	)
Investments in an unrealized loss position	$	10,070	$	(730	)	$	10,070	$	(730	)

The Company did not have any investments in an unrealized loss position for less than twelve months as of December 31, 2018 and 2017, respectively.