15. INTEREST EXPENSE

Interest expense comprised the following for the years ended December 31, 2017, 2016 and 2015:



	For The Year Ended December 31,
	2017		2016		2015
Interest on long-term debt and other financing arrangements	$	64,855	$	89,602	$	95,419
Amortization of capitalized debt issuance costs	5,778		8,842		15,118
Amortization of debt issuance discount	—		12,945		41,230
Total interest expense	$	70,633	$	111,389	$	151,767

We paid cash interest (including mandatory cash-pay Guarantee Fees) of US$ 40.6 million, US$ 50.6 million and US$ 15.0 million during the years ended December 31, 2017, 2016 and 2015, respectively. In addition, we paid US$ 1.7 million and US$ 7.5 million of Guarantee Fees in cash during the years ended December 31, 2017 and 2016, respectively, for which we had the option to pay in kind. Interest expense related to a portion of the 2018 Euro Term Loan has been allocated to results from discontinued operations (see Note 3, "Discontinued Operations and Assets Held for Sale").