Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation (Schedule of Share-based Compensation Expense) (Details)

v3.10.0.1
Share-Based Compensation (Schedule of Share-based Compensation Expense) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based $ 9,460 $ 10,225 $ 4,536
Share-based compensation expense - Liability-based 336 4,294 12,285
Settled share-based awards 0 6,351 0
Share-based compensation - capitalized oil and gas properties 3,434 3,202 7,274
General and Administrative Expense      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation 6,362 4,966 9,547
CFO      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Settled share-based awards   6,351  
RSU equity awards      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 9,460 10,225 4,536
Share-based compensation expense - Liability-based 0 0 0
Cash-settleable RSU awards      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 0 0 0
Share-based compensation expense - Liability-based $ 336 $ 4,294 $ 12,285