XML 100 R78.htm IDEA: XBRL DOCUMENT v3.19.1
Commitments And Contingencies (Firm Delivery Contracts) (Details)
$ in Thousands
Dec. 31, 2018
USD ($)
Other Commitments [Line Items]  
Firm Delivery Contracts $ 100
Firm Delivery Contracts  
Other Commitments [Line Items]  
2019 1,551
2020 1,556
2021 1,551
Firm Delivery Contracts $ 4,658