Debt

Collectively, our credit facility is comprised of a term loan with a face amount of $545.0 million, maturing on October 19, 2022 (the “Senior Secured Term Loan”); a term loan with a face amount of $300.0 million, maturing on April 3, 2021 (the Incremental Term Loan”); and a revolving line of credit with a face amount of $143.0 million, maturing on October 19, 2020 (the “Senior Secured Revolver”). The credit facility is collateralized by all of our assets.

The following table presents debt balances as of March 31, 2019, and December 31, 2018.



	March 31, 2019		December 31, 2018
Senior Secured Term Loan	$	530,625	$	532,063
Incremental Term Loan	276,000		279,000
Senior Secured Revolver	56,184		38,720
International lines of credit and other loans	10,601		9,810
Total principal	873,410		859,593
Less—current maturities of long-term debt	33,444		31,280
Principal, net of current portion	839,966		828,313
Less—unamortized debt issuance costs	13,692		16,842
Long-term debt, net of current portion	$	826,274	$	811,471

We capitalized interest costs amounting to $0.6 million and $0.2 million in the three months ended March 31, 2019 and 2018, respectively, related to construction in progress.

Senior Secured Term Loan

Outstanding borrowings under the Senior Secured Term Loan bear interest at the greater of 0.75% or one-month London Interbank Offered Rate (“LIBOR”) plus an applicable margin of 3.75%. At March 31, 2019, the Senior Secured Term Loan bore interest at 6.24%.

Incremental Term Loan

Outstanding borrowings under the Incremental Term Loan bear interest at one-month LIBOR plus an applicable margin of 3.25%. At March 31, 2019, the Incremental Term Loan bore interest of 5.74%.

Senior Secured Revolver

Outstanding borrowings under the Senior Secured Revolver bear interest at one-month LIBOR plus an applicable margin of 3.50%. At March 31, 2019, the Senior Secured Revolver bore interest of 5.99%. We pay an annual commitment fee of 0.50% for unused capacity under the Senior Secured Revolver on a quarterly basis.

Total available capacity under the Senior Secured Revolver was $125.0 million as of March 31, 2019. Our credit facility is subject to certain financial covenants based on a consolidated net leverage ratio, as defined in the credit facility agreement. The financial covenants are effective when we have outstanding borrowings under our Senior Secured Revolver on the last day of any fiscal quarter, become more restrictive over time, and are dependent upon our operational and financial performance. If our operational or financial performance is below our expectations, we may be required to take actions to reduce expenditures and decrease our net indebtedness to maintain compliance in future periods. We had $56.2 million outstanding under the Senior Secured Revolver at March 31, 2019, and we were in compliance with all covenants under our credit facility.

On March 15, 2019, we amended our existing credit facility (the “March 2019 amendment”) to amend the defined terms within the credit facility. We paid $0.8 million of debt issuance costs related to the March 2019 amendment which was recorded as a direct reduction to the carrying amount of the associated long-term debt. We also wrote-off $2.7 million of unamortized debt issuance costs related to the modification of the credit facility.

Derivative Instruments and Hedging Activities

In February 2019, we entered into a $700.0 million amortizing notional amount fixed-rate interest rate swap agreement to manage the interest rate risk associated with our long-term variable-rate debt until 2022. The fixed-rate interest rate swap agreement calls for us to receive interest monthly at a variable rate equal to one-month LIBOR and to pay interest monthly at a fixed rate of 2.4575%. Refer to Note 16 for further discussion of the interest rate swap agreement.