	March 31,		December 31,
	2020		2019
Loan Agreement	$	—	$	—
4.67% Senior Unsecured Notes due January 15, 2021		40,000		40,000
5.25% Senior Unsecured Notes due January 15, 2024		11,000		11,000
5.30% Senior Unsecured Notes due January 15, 2024		15,000		15,000
5.45% Senior Unsecured Notes due January 15, 2026		12,000		12,000
		78,000		78,000
Less unamortized deferred financing costs		725		824
		77,275		77,176
Less current portion long-term debt		39,937		—
Long-term debt	$	37,338	$	77,176

In March 2017, the Company entered into a Fifth Amended and Restated Loan Agreement (the “Loan Agreement”). The Loan Agreement amended the pre-existing senior revolving credit facility’s borrowing limit to $200 million, inclusive of letters of credit, and extended the maturity date from December 2018 to March 2022. As of March 31, 2020, the Company had $194.2 million available under the Loan Agreement. The Company had $5.8 million of letters of credit issued related to insurance and other contracts requiring financial assurance in the ordinary course of business, including the $2 million provided to the EPA as discussed in Note 12. Borrowings under the Loan Agreement bear interest at the LIBOR rate, prime rate, federal funds effective rate, the Canadian deposit offered rate, or the euro currency reference rate depending on the type of loan requested by the Company, plus the applicable margin as set forth in the Loan Agreement.

The Company also holds Senior Unsecured Notes (“Notes”), which range in face value from $11 million to $40 million, with interest rates ranging from 4.67% to 5.45%, payable semiannually, and maturing between January 2021 and January 2026. At March 31, 2020, $78 million of the Notes were outstanding.

The weighted average interest rate on borrowings under the Company’s long-term debt was 6.24% and 6.23% for the quarters ended March 31, 2020 and 2019, respectively, which includes a quarterly facility fee on the used and unused portion, as well as amortization of deferred financing costs.

As of March 31, 2020, the Company was in compliance with all of its debt covenants associated with its Loan Agreement and Notes. The most restrictive financial covenants for all of the Company’s debt are an interest coverage ratio (defined as earnings before interest, taxes, depreciation and amortization, as adjusted, divided by interest expense) and a leverage ratio (defined as total debt divided by earnings before interest, taxes, depreciation and amortization, as adjusted).