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Long-Term Debt (Details) - Line of Credit - USD ($)
3 Months Ended
Mar. 31, 2017
Apr. 28, 2017
Revolving Credit Facility    
Debt Instrument [Line Items]    
Commitment amount $ 500,000,000.0  
Automatic decrease in borrowing base 25.00%  
Current borrowing capacity $ 250,000,000  
Remaining borrowing capacity 249,600,000  
Revolving Credit Facility | Subsequent Event    
Debt Instrument [Line Items]    
Current borrowing capacity   $ 350,000,000
Letter of Credit    
Debt Instrument [Line Items]    
Commitment amount 15,000,000.0  
Letters of credit outstanding $ 400,000