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Goodwill and Intangible Assets, Net (Narrative) (Detail)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2017
USD ($)
segment
Dec. 31, 2016
USD ($)
Mar. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]        
Number of operating segments | segment 6      
Goodwill impairment charge $ 77,343      
Goodwill 4,529,645 $ 4,390,261 $ 1,424,591 $ 1,422,825
Property and equipment, net 4,721,669 4,738,055    
Indefinite-lived intangible assets $ 216,392 216,392    
Long-term Franchise Agreements and Contracts [Member]        
Acquired Finite-Lived Intangible Assets [Line Items]        
Weighted average amortization period of acquired intangible assets 19 years 2 months 12 days      
Customer Lists [Member]        
Acquired Finite-Lived Intangible Assets [Line Items]        
Weighted average amortization period of acquired intangible assets 10 years      
Permits and Other [Member]        
Acquired Finite-Lived Intangible Assets [Line Items]        
Weighted average amortization period of acquired intangible assets 40 years      
Exploration and Production [Member]        
Acquired Finite-Lived Intangible Assets [Line Items]        
Fair value discount rate 11.70%      
Goodwill impairment charge $ 77,343 0    
Goodwill 77,343 77,343 $ 77,343 $ 77,343
Exploration and Production Facility Permits [Member]        
Acquired Finite-Lived Intangible Assets [Line Items]        
Indefinite-lived intangible assets $ 21,348 $ 21,348