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Summary of Significant Accounting Policies - Narrative (Details)
12 Months Ended
Dec. 31, 2016
USD ($)
Customer
Institution
Segment
Dec. 31, 2015
USD ($)
Customer
Dec. 31, 2014
USD ($)
Customer
Jan. 01, 2017
USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]        
Number of operating segments | Segment 1      
Number of financial institutions | Institution 2      
Amortization of unproved properties included in depreciation, depletion, and amortization $ 25,000,000 $ 41,400,000 $ 17,400,000  
Assets legally restricted for purposes of settling asset retirement obligations 0      
Properties and Equipment        
Net cash provided by operating activities 392,377,000 740,737,000 1,236,435,000  
Net cash provided by financing activities $ (458,869,000) $ (232,157,000) $ (425,959,000)  
Gathering and pipeline systems and equipment | Minimum        
Properties and Equipment        
Estimated useful life 10 years      
Gathering and pipeline systems and equipment | Maximum        
Properties and Equipment        
Estimated useful life 25 years      
Pipeline and transmission systems | Minimum        
Properties and Equipment        
Estimated useful life 12 years      
Pipeline and transmission systems | Maximum        
Properties and Equipment        
Estimated useful life 25 years      
Gathering and compression equipment | Maximum        
Properties and Equipment        
Estimated useful life 10 years      
Storage equipment and facilities | Minimum        
Properties and Equipment        
Estimated useful life 10 years      
Storage equipment and facilities | Maximum        
Properties and Equipment        
Estimated useful life 16 years      
Buildings | Minimum        
Properties and Equipment        
Estimated useful life 25 years      
Buildings | Maximum        
Properties and Equipment        
Estimated useful life 40 years      
Other assets | Minimum        
Properties and Equipment        
Estimated useful life 3 years      
Other assets | Maximum        
Properties and Equipment        
Estimated useful life 10 years      
Sales Revenue, Net | Customer        
Concentration Risk [Line Items]        
Number of customers | Customer 2 2 2  
Accounting Standards Update 2016-09        
Properties and Equipment        
Net cash provided by operating activities $ 5,100,000 $ 8,900,000    
Net cash provided by financing activities $ 5,100,000 $ 8,900,000    
Subsequent Event | Accounting Standards Update 2016-09        
Properties and Equipment        
Cumulative effect adjustment       $ 42,200,000
Customer one | Sales Revenue, Net | Customer        
Concentration Risk [Line Items]        
Percentage of total sales 19.00% 16.00% 14.00%  
Customer two | Sales Revenue, Net | Customer        
Concentration Risk [Line Items]        
Percentage of total sales 10.00% 14.00% 10.00%