
	December 31,
(in thousands)	2020		2019
9.25% Senior Secured Notes, due June 2023 (1)(2)	$	645,000	$	645,000
6.50% Senior Notes, due April 2021, net of current portion (3)	—		$	2,240
Unamortized discount and debt issuance costs (4)	(11,058)		(14,834)

Total long-term debt	633,942		632,406
Current portion of long-term debt (3)	2,240		—
Total long-term debt, including current portion	$	636,182	$	632,406

(1)This debt was issued at a $16.1 million discount which is being amortized, as interest expense, over the remaining term of the debt. Debt issuance costs associated with this debt totaled $9.4 million.

(2)The estimated fair value of total long-term debt outstanding was approximately $645.7 million and $673.8 million as of December 31, 2020 and 2019, respectively. This estimate of fair value is a Level 2 measurement as it was determined by quotations obtained from a broker-dealer who makes a market in these and similar securities.

(3)The 6.50% Senior Notes, due April 2021, mature within 12 months, and, therefore, the outstanding balance of $2.2 million has been classified as short-term as of December 31, 2020.

(4)For the years ended December 31, 2020, 2019, and 2018, amortization of the discount on debt and amortization of deferred financing costs reported as Interest expense, net totaled approximately $3.8 million, $3.4 million, and $3.1 million, respectively.


(in thousands)	Total Capacity		Amount borrowed as of December 31, 2020		Outstanding Letters of Credit		Available capacity as of December 31, 2020		Maturity Date
ABL Credit Agreement (1)(2)	$	20,146	$	—	$	—	$	20,146	September 30, 2022

(1)At the option of the borrowers, loans under the ABL Credit Agreement initially bear interest at an annual rate equal to (i) 1.00% plus a base rate, Thereafter, loans will bear interest (i) at such rates if our quarterly excess availability is greater than 50% and (ii) 1.50% plus a base rate, otherwise.

(2)The ABL Credit Agreement was amended on September 29, 2020 to, among other things, reduce the commitments thereunder to $35 million and extended the maturity date to September 30, 2022. Deferred financing costs of $0.4 million were capitalized related to this amendment and will be amortized from Prepaid expenses and other current assets and Other long-term assets over the remaining term of the ABL Credit Agreement. Amortization expense was $0.2 million for the years ended December 31, 2020, 2019, and 2018.