	June 30, 2019			December 31, 2018
Borrowings under the ABL Credit Agreement	$	270.0		$	59.0
11.25% senior notes due February 1, 2019 ^(a)		—			172.2
7.625% senior notes due June 15, 2020		65.8			65.8
7.875% senior notes due March 15, 2021		190.4			190.4
8.875% debentures due April 15, 2021		81.0			81.0
7.00% senior notes due February 15, 2022		140.0			140.0
6.50% senior notes due November 15, 2023		290.6			290.6
Term Loan Credit Agreement due January 15, 2024 ^(b)		542.5			544.7
6.00% senior notes due April 1, 2024		298.3			298.3
6.625% debentures due April 15, 2029		157.9			157.9
8.820% debentures due April 15, 2031		69.0			69.0
Other ^(c)		30.5			38.9
Unamortized debt issuance costs		(14.6	)		(16.3	)
Total debt		2,121.4			2,091.5
Less: current portion		101.7			216.2
Long-term debt	$	2,019.7		$	1,875.3

The fair values of the senior notes and debentures, which were determined using the market approach based upon interest rates available to us for borrowings with similar terms and maturities, were determined to be Level 2 under the fair value hierarchy. The fair value of our total debt was less than its book value by approximately $16.4 million and $14.4 million at June 30, 2019 and December 31, 2018, respectively.

On February 1, 2019, we retired the $172.2 million 11.25% senior notes using availability under our asset-based revolving credit facility (the “ABL Credit Agreement”).

On October 15, 2018, we entered into a $550.0 million senior secured Term Loan B credit facility pursuant to a credit agreement (the “Term Loan Credit Agreement”). Proceeds from the Term Loan Credit Agreement, net of a $5.5 million discount, were used to repurchase certain senior notes, pay transaction fees and repay a portion of borrowings under the ABL Credit Agreement.

Our obligations under the Term Loan Credit Agreement are guaranteed by our material domestic subsidiaries (the “Guarantors”) and are secured by a security interest in substantially all assets of ours and the Guarantors, including certain material real property, subject to certain exceptions and exclusions. The ABL Priority Collateral secures our obligations and the obligations of the Guarantors under the Term Loan Credit Agreement and related guarantees on a second-priority basis, and all other collateral other than the ABL Priority Collateral secures our obligations and the obligations of the Guarantors under the Term Loan Credit Agreement and related guarantees on a first-priority basis, in each case, subject to permitted liens.

The Term Loan Credit Agreement contains customary affirmative and negative covenants including negative covenants restricting, among other things, our ability to incur debt, make investments, make certain restricted payments (including payments on certain other debt and external dividends), incur liens securing other debt, consummate certain fundamental transactions, enter into transactions with affiliates and consummate asset sales. The Term Loan Credit Agreement requires that the net cash proceeds of significant asset sales be used to prepay borrowings under the Term Loan Credit Agreement, except in certain circumstances, including the reinvestment of net cash proceeds in assets useful to our business, repayment of borrowings under our ABL Credit Agreement or the funding of debt tenders, in each case, subject to certain restrictions and limitations set forth in the Term Loan Credit Agreement.

The Term Loan Credit Agreement is scheduled to mature on January 15, 2024, at which time all amounts outstanding under the Term Loan Credit Agreement will be due and payable. Principal payments of $1.4 million are due quarterly. Borrowings will bear interest at a Eurocurrency rate plus a margin of 5% or a base rate plus a margin of 4%.

On October 15, 2018, we repurchased $172.6 million and $257.4 million in aggregate principal amount of the 7.625% senior notes due 2020 and 7.875% senior notes due 2021, respectively, pursuant to a tender offer. We recorded a loss on debt extinguishment of $32.3 million in the fourth quarter of 2018 on the repurchase of the bonds, representing tender premiums paid of $29.0 million, write-off of unamortized debt issuance costs of $1.5 million and fees and expenses of $1.8 million.

On September 29, 2017, we entered into the ABL Credit Agreement which amended and restated our prior $800.0 million senior secured revolving credit facility dated September 30, 2016. The ABL Credit Agreement provides for a senior secured asset-based revolving credit facility of up to $800.0 million. The amount available to be borrowed under the ABL Credit Agreement is equal to the lesser of (a) $800.0 million and (b) a borrowing base formula based on the amount of accounts receivable, inventory, machinery, equipment and, if we were to so elect in the future subject to the satisfaction of certain conditions, fee-owned real estate of ours and the Guarantors, subject to certain eligibility criteria and advance rates (collectively, the “Borrowing Base”). The aggregate amount of real estate, machinery and equipment that can be included in the Borrowing Base cannot exceed $200.0 million.

On October 15, 2018, we entered into Amendment No. 1 to the ABL Credit Agreement, which amended the ABL Credit Agreement to, among other things, permit (i) the incurrence of the debt pursuant to the Term Loan Credit Agreement and (ii) the incurrence of a lien on the ABL Priority Collateral to secure our obligations under the Term Loan Credit Agreement and related guarantees on a second-priority basis.

Our obligations under the ABL Credit Agreement are guaranteed by the Guarantors and are secured by a security interest in substantially all assets of ours and the Guarantors, including, only to the extent included in the Borrowing Base, real property, in each case subject to certain exceptions and exclusions. The assets of ours and the Guarantors consisting of accounts receivable, inventory, deposit accounts, securities accounts, machinery and equipment and, to the extent related to the foregoing, general intangibles, documents and instruments, as well as 65% of the equity interests of our first-tier foreign subsidiaries (collectively, the “ABL Priority Collateral”), secure our obligations and the obligations of the Guarantors under the ABL Credit Agreement and the related guarantees on a first-priority basis, and all other collateral other than the ABL Priority Collateral secures our obligations and the obligations of the Guarantors under the ABL Credit Agreement on a second-priority basis, in each case, subject to permitted liens.

The ABL Credit Agreement contains customary restrictive covenants, including a covenant which requires us to maintain a minimum fixed charge coverage ratio under certain circumstances. In addition, our ability to undertake certain actions, including, among other things, prepay certain junior debt, incur additional indebtedness and make certain restricted payments (including external dividends) depends on satisfaction of certain conditions, including, among other things, meeting minimum borrowing availability thresholds under the ABL Credit Agreement.

Borrowings under the ABL Credit Agreement bear interest at a rate dependent on the average quarterly availability under the ABL Credit Agreement and is calculated according to a base rate (except in certain circumstances, based on the prime rate) or a Eurocurrency rate (except in certain circumstances, based on London Inter-bank Offered Rate or “LIBOR”) plus an applicable margin. The applicable margin for base rate loans ranges from 0.25% to 0.50% and the applicable margin for Eurocurrency loans ranges from 1.25% to 1.50%. In addition, a fee is payable quarterly on the unused portion of the amount available to be borrowed under the ABL Credit Agreement. The fee accrues at a rate of either 0.25% or 0.375% depending upon the average usage of the facility.

The ABL Credit Agreement is scheduled to mature on September 29, 2022, at which time all outstanding amounts under the ABL Credit Agreement will be due and payable. Borrowings under the ABL Credit Agreement may be used for working capital and general corporate purposes.

Based on our borrowing base as of June 30, 2019 and existing borrowings, we had approximately $397.2 million borrowing capacity available under the ABL Credit Agreement.

The weighted average interest rate on borrowings under our current facility was 3.7% and 3.4% during the six months ended June 30, 2019 and 2018, respectively.

Interest paid, net of interest capitalized, was $47.4 million and $85.5 million for the three and six months ended June 30, 2019, respectively, and $43.7 million and $81.8 million for the three and six months ended June 30, 2018, respectively.

Interest income was $0.9 million and $1.7 million for the three and six months ended June 30, 2019, respectively, and $0.7 million and $1.2 million for the three and six months ended June 30, 2018, respectively.