XML 56 R44.htm IDEA: XBRL DOCUMENT v3.21.1
Debt - Credit Facility (Details)
Mar. 31, 2021
USD ($)
U.S. revolving credit facility [Member]  
Line of Credit Facility [Line Items]  
Credit facility maximum amount $ 175,000,000.0
Borrowing availability 139,600,000
Outstanding letters of credit issued 75,400,000
Outstanding borrowings 50,400,000
Borrowing availability, net of borrowings 13,800,000
Iceland revolving line of credit [Member] | Long-term Debt [Member]  
Line of Credit Facility [Line Items]  
Credit facility maximum amount 50,000,000.0
Borrowing availability 50,000,000.0
Outstanding letters of credit issued 0
Outstanding borrowings 0
Borrowing availability, net of borrowings $ 50,000,000.0