At March 31, 2024 and December 31, 2023, debt was comprised of the following:


(In thousands)	Maturity Dates	March 31, 2024		December 31, 2023
Senior unsecured notes
3.95% (net of unamortized debt issuance cost of $168 and $191 for 2024 and 2023, respectively)	2024-2027	$	56,975	$	56,952
3.86% (net of unamortized debt issuance cost of $81 and $105 for 2024 and 2023, respectively)	2024-2025		28,490		28,466
2.30% (net of unamortized debt issuance cost of $126 and $142 for 2024 and 2023, respectively)	2024-2028		49,874		49,858
2.37% (net of unamortized debt issuance cost of $132 and $148 for 2024 and 2023, respectively)	2024-2028		49,868		49,852
2.73% (net of unamortized debt issuance cost of $149 and $175 for 2024 and 2023, respectively)	2025-2031		99,851		99,825
2.83% (net of unamortized debt issuance cost of $116 and $134 for 2024 and 2023, respectively)	2026-2032		74,884		74,866
Revolving credit facility and term loan borrowing	2024		280,000		283,000
Debt of foreign subsidiaries
Unsecured bank debt, foreign currency	2024		6,040		11,327
Total debt		$	645,982	$	654,146
Less current maturities			245,861		252,898
Long-term debt		$	400,121	$	401,248

The Company's long-term debt financing is comprised of certain senior unsecured notes issued to insurance companies in private placement transactions pursuant to note purchase agreements (the “Note Purchase Agreements”), totaling $359,942,000 as of March 31, 2024. These notes are denominated in U.S. dollars and have fixed interest rates ranging from 2.30 percent to 3.95 percent. The notes had original maturities of seven to 12 years with mandatory principal payments beginning four, five and six years after issuance. The Company will be required to make principal payments on the currently outstanding notes from 2024 to 2032.

The Company's credit agreement (the "Credit Agreement") with a syndicate of banks provides for credit facilities in an initial aggregate principal amount of $450,000,000, consisting of (a) a $350,000,000 multi-currency revolving credit facility and (b) a $100,000,000 delayed draw term loan credit facility, each of which matures on June 24, 2027. The Company maintains import letters of credit, and standby letters of credit under its workers’ compensation insurance agreements and for other purposes, as needed from time to time, which are issued under the revolving credit agreement. As of March 31, 2024, the Company had outstanding letters of credit totaling $10,979,000 and $280,000,000 of outstanding borrowings under the credit agreement, inclusive of a $93,750,000 delayed draw term loan ($6,250,000 of the term loan principal has been permanently repaid as scheduled). There was $152,771,000 available under the credit agreement as of March 31, 2024.

The Company’s material debt agreements contain provisions which, among other covenants, require maintenance of certain financial ratios and place limitations on additional debt, investments and payment of dividends. Based on the loan agreement provisions that place limitations on dividend payments, unrestricted retained earnings (i.e., retained earnings available for dividend distribution) were $240,735,000 and $234,399,000 at March 31, 2024 and December 31, 2023, respectively.