Debt (Tables)

3 Months Ended

Mar. 31, 2017

Debt Disclosure [Abstract]

Schedule of Debt

	March 31, 2017		December 31, 2016
Debt classified as current liabilities:
Hancock County industrial revenue bonds ("IRBs") due 2028, interest payable quarterly (variable interest rates (not to exceed 12%)) (1)	$	7,815	$	7,815
Debt classified as non-current liabilities:
7.5% senior secured notes due June 1, 2021, net of debt discount of $2,191 and $2,301, respectively, interest payable semiannually	247,809		247,699
Total	$	255,624	$	255,514

(1) The IRBs are classified as current liabilities because they are remarketed weekly and could be required to be repaid upon demand if there is a failed remarketing. The IRB interest rate at March 31, 2017 was 1.11%.

Schedule of Line of Credit Facilities

Status of our Iceland revolving credit facility:

	March 31, 2017
Credit facility maximum amount	$	50,000
Borrowing availability	50,000
Outstanding borrowings	—
Borrowing availability, net of borrowings	50,000

Status of our U.S. revolving credit facility:

	March 31, 2017
Credit facility maximum amount	$	150,000
Borrowing availability	115,288
Outstanding letters of credit issued	65,764
Outstanding borrowings	—
Borrowing availability, net of outstanding letters of credit and borrowings	49,524