	March 31, 2019			December 31, 2018
Revolving Credit and Security Agreement	$	40,037		$	14,320
Sale and leaseback financing obligation		18,626			18,518
Promissory notes (and interest)		0			26,205
Industrial Revenue Bonds ("IRB")		13,311			13,311
Minority shareholder loan		3,858			4,056
Finance lease liabilities		1,485			1,199
Outstanding borrowings		77,317			77,609
Debt – current portion		(19,256	)		(45,728	)
Long-term debt	$	58,061		$	31,881

The Corporation is party to a five-year Revolving Credit and Security Agreement (the “Credit Agreement”) with a syndicate of banks, which expires in May 2021. The Credit Agreement provides for initial borrowings not to exceed $100,000, with an option to increase the credit facility by an additional $50,000 at the request of the Corporation and with the approval of the banks. The Credit Agreement includes sublimits for letters of credit not to exceed $40,000, European borrowings not to exceed $15,000, and Canadian borrowings not to exceed $15,000.

Availability under the Credit Agreement is based on eligible accounts receivable, inventory and fixed assets. Amounts outstanding under the credit facility bear interest, at the Corporation’s option, at either (i) LIBOR plus an applicable margin ranging between 1.75% to 2.25% based on the quarterly average excess availability or (ii) the base rate plus an applicable margin ranging between 0.75% to 1.25% based on the quarterly average excess availability. Additionally, the Corporation is required to pay a commitment fee ranging between 0.25% and 0.375% based on the daily unused portion of the credit facility. As of March 31, 2019, the Corporation had outstanding borrowings under the Credit Agreement of $40,037 (including £3,000 of European borrowings for its U.K. subsidiary). Outstanding borrowings increased from December 31, 2018, to March 31, 2019, due to additional borrowings used to repay promissory notes in March 2019. The average interest rate for the three months ended March 31, 2019, was approximately 2.22%. Additionally, the Corporation had utilized a portion of the credit facility for letters of credit (Note 9). As of March 31, 2019, remaining availability under the Credit Agreement approximated $39,000, net of standard availability reserves.

Borrowings outstanding under the Credit Agreement are collateralized by a first priority perfected security interest in substantially all of the assets of the Corporation and its subsidiaries (other than real property). Additionally, the Credit Agreement contains customary affirmative and negative covenants and limitations, including, but not limited to, investments in certain of its subsidiaries, payment of dividends, incurrence of additional indebtedness, upstream distributions from subsidiaries, and acquisitions and divestures. The Corporation must also maintain a certain level of excess availability. If excess availability falls below the established threshold, or in an event of default, the Corporation will be required to maintain a minimum fixed charge coverage ratio of not less than 1.00 to 1.00. The Corporation was in compliance with the applicable bank covenants as of March 31, 2019.

In September 2018, UES completed a sale and leaseback financing transaction for certain of its real property, including its manufacturing facilities in Valparaiso, Indiana and Burgettstown, Pennsylvania, and its manufacturing facility and corporate headquarters located in Carnegie, Pennsylvania (the “Properties”). Simultaneously with the sale, UES entered into a lease agreement pursuant to which UES leased the Properties from the buyer. The lease provides for an initial term of 20 years; however, UES may extend the lease for four successive periods of approximately five years each. If fully extended, the lease would expire in September 2058. UES also has the option to repurchase the Properties, which it may exercise in 2025, for a price equal to the greater of (i) their Fair Market Value, or (ii) 115% of Lessor’s Total Investment for the Facilities, with such terms defined in the lease agreement. The effective interest rate approximated 6% for the three months ended March 31, 2019.

In connection with a March 2016 acquisition, the Corporation issued two three-year promissory notes. Principal and accrued interest of $26,474, in the aggregate, were paid on March 4, 2019, using additional borrowings under the Credit Agreement.