15. INTEREST EXPENSE

Interest expense comprised the following for the years ended December 31, 2018, 2017 and 2016:



	For The Year Ended December 31,
	2018		2017		2016
Interest on long-term debt and other financing arrangements	$	44,604	$	77,170	$	104,361
Amortization of capitalized debt issuance costs	4,502		6,018		9,072
Amortization of debt issuance discount	—		—		12,945
Total interest expense	$	49,106	$	83,188	$	126,378

We paid cash interest (including mandatory cash-pay Guarantee Fees) of US$ 43.4 million, US$ 47.2 million and US$ 54.0 million during the years ended December 31, 2018, 2017 and 2016, respectively. In addition, we paid US$ 27.3 million and US$ 22.4 million of accrued Guarantee Fees during the years ended December 31, 2018 and 2016, respectively, which we had previously elected to pay in kind and US$ 0.8 million, US$ 8.3 million and US$ 8.3 million of Guarantee Fees in cash during the years ended December 31, 2018, 2017 and 2016, respectively, for which we had the option to pay in kind. Interest expense related to the 2019 Euro Loan and the 2021 Euro Loan has been allocated to results from discontinued operations relative to the proportion of the principal balance that was repaid from the proceeds of the Croatian Transaction (see Note 3, "Discontinued Operations and Assets Held for Sale").