Quarterly report pursuant to Section 13 or 15(d)

LONG-TERM DEBT (Narrative) (Details)

v3.19.3
LONG-TERM DEBT (Narrative) (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Jun. 03, 2019
Dec. 31, 2018
Debt Instrument [Line Items]            
Debt issuance costs, net $ 26,052,000   $ 26,052,000     $ 30,733,000
Capitalized interest expense, undeveloped properties 1,000,000.0 $ 1,600,000 2,800,000 $ 4,000,000.0    
Gain on debt extinguishment (23,600,000) $ 0 (23,600,000) $ 0    
Revolving Credit Facility            
Debt Instrument [Line Items]            
Aggregate principal amount 104,400,000   104,400,000      
Repurchase amount 80,300,000   80,300,000      
Gain on debt extinguishment     (23,600,000)      
Construction loan            
Debt Instrument [Line Items]            
Debt issuance costs, net 100,000   100,000      
6.000% senior unsecured notes due 2024 | Senior notes            
Debt Instrument [Line Items]            
Long-term debt $ 630,796,000   $ 630,796,000     650,000,000
Stated interest rate, percent 6.00%   6.00%      
Debt issuance costs, net $ 7,500,000   $ 7,500,000      
Aggregate principal amount 19,200,000   19,200,000      
6.625% senior unsecured notes due 2023 | Senior notes            
Debt Instrument [Line Items]            
Long-term debt $ 340,000,000   $ 340,000,000     350,000,000
Stated interest rate, percent 6.625%   6.625%      
Debt issuance costs, net $ 3,600,000   $ 3,600,000      
Aggregate principal amount 10,000,000.0   10,000,000.0      
6.375% senior unsecured notes due 2025 | Senior notes            
Debt Instrument [Line Items]            
Long-term debt $ 577,268,000   $ 577,268,000     600,000,000
Stated interest rate, percent 6.375%   6.375%      
Debt issuance costs, net $ 10,800,000   $ 10,800,000      
Aggregate principal amount 22,700,000   22,700,000      
6.375% senior unsecured notes due 2026 | Senior notes            
Debt Instrument [Line Items]            
Long-term debt $ 397,529,000   $ 397,529,000     450,000,000
Stated interest rate, percent 6.375%   6.375%      
Debt issuance costs, net $ 4,000,000.0   $ 4,000,000.0      
Aggregate principal amount 52,500,000   $ 52,500,000      
Nova Scotia, Amegy, KeyBank | Revolving credit agreement            
Debt Instrument [Line Items]            
Credit facility interest rate at the eurodollar rate     3.52%      
Nova Scotia, Amegy, KeyBank | Revolving credit agreement | Revolving credit agreement            
Debt Instrument [Line Items]            
Borrowing base         $ 1,400,000,000  
Elected commitment amount         $ 1,000,000,000.0  
Long-term debt 135,000,000   $ 135,000,000     $ 45,000,000
Remaining borrowing capacity 616,400,000   616,400,000      
Nova Scotia, Amegy, KeyBank | Letter of credit | Revolving credit agreement            
Debt Instrument [Line Items]            
Credit facility outstanding $ 248,600,000   $ 248,600,000