Long-term debt, net of unamortized debt issuance costs, consisted of the following:


	December 31,
(In thousands)	2023			2022
Senior notes	$	79,977		$	99,963
Revolving credit facility		—			—
Total long-term debt		79,977			99,963
Less: Current maturities		(20,000	)		(20,000	)
Total maturities due after one year	$	59,977		$	79,963

On May 4, 2020, we entered into a Note Purchase and Private Shelf Agreement with PGIM, Inc. (“Prudential”) and certain affiliates and managed accounts of Prudential (as subsequently amended on March 22, 2023, the “Note Agreement”). The Note Agreement, which is uncommitted and subject to Prudential’s sole discretion, provides for the issuance of senior promissory notes with an aggregate principal amount of up to $350.0 million through March 22, 2026. On May 4, 2020, we issued $100.0 million aggregate principal amount of senior promissory notes (the “Series B Notes”). Borrowing availability under the Note Agreement is reduced by the outstanding amount of the existing Series B Notes, and all other senior promissory notes issued pursuant to the Note Agreement.

The Series B Notes bear interest at 3.10% per annum and mature on May 4, 2027, unless prepaid. The first principal payment of $20.0 million was paid on May 4, 2023. The remaining $80.0 million will be paid in four equal annual installments of $20.0 million through May 4, 2027. The Series B Notes are senior unsecured obligations and rank pari passu with borrowings under our third amended and restated credit agreement, dated March 22, 2023, with Wells Fargo Bank, National Association serving as administrative agent for the lenders (the “Credit Agreement”) or other senior promissory notes issued pursuant to the Note Agreement.

The Credit Agreement provides for a five-year, $250.0 million senior unsecured revolving line of credit and a $150.0 million accordion feature, which if fully exercised and approved, would expand the total borrowing capacity up to an aggregate of $400.0 million. Of the $250.0 million line of credit commitments under the Credit Agreement, up to $100.0 million may be used for letters of credit.

At our option, borrowings under the Credit Agreement bear interest at either: (i) the Secured Overnight Financing Rate (SOFR) plus the Term SOFR Adjustment, as defined in the Credit Agreement, equal to 0.100%, plus an applicable margin that ranges from 1.000% to 1.375%; or (ii) a Base Rate, as defined in the Credit Agreement, plus an applicable margin that ranges from 0.000% to 0.375%. The applicable margin for each of the foregoing options is dependent upon our consolidated debt to consolidated total capitalization ratio. Letter of credit fees equal to the applicable margin for SOFR loans are charged quarterly in arrears on the daily average aggregate stated amount of all letters of credit outstanding during the quarter. Commitment fees ranging from 0.090% to 0.175% (based upon our consolidated debt to total consolidated capitalization ratio) are charged quarterly in arrears on the aggregate unutilized portion of the Credit Agreement.

For periods covered under the Credit Agreement, the applicable margin on SOFR loans and letter of credit fees were 1.000% and commitment fees were 0.090%.

The Credit Agreement replaced our previous five-year, $250.0 million senior unsecured revolving credit agreement dated as of November 21, 2019 (the “Prior Credit Agreement”). For periods in 2023 and 2022 covered under the Prior Credit Agreement, the applicable margin on LIBOR loans and letter of credit fees was 1.000% and commitment fees were 0.100%.

There were $40.0 million and $38.7 million of outstanding letters of credit at December 31, 2023 and 2022, respectively.

The Credit Agreement and Note Agreement contain customary covenants, including financial covenants that require us to observe a maximum ratio of debt to total capital and a minimum fixed charge coverage ratio. The Credit Agreement and Note Agreement also include a provision limiting our ability to make restricted payments, including dividends and payments for share repurchases, unless, among other conditions, no defaults or events of default are ongoing (or would be caused by such restricted payment).