Equity and Distributions - Summary of Previous Owners' Equity Transactions (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Equity Structure And Transactions [Line Items]                      
Balance       $ 863,021       $ 864,863 $ 863,021 $ 864,863 $ 891,483
Net income (loss) 158,839 101,307 (111,640) (32,892) 1,029 12,098 56,413 (8,535) 115,614 61,005 23,067
Contributions                 6,560 97,324 64,803
Contribution of oil and gas properties                     6,893
Distribution attributable to net assets acquired                 (2,413) (502,920) (260,663)
Contribution related to sale of assets to NGP affiliate                     40,138
Net book value of net assets acquired by NGP affiliate                     (33,859)
Distributions                 (164,738) (127,741) (62,922)
Distribution of net asset to MRD Holdco                 (26,131)    
Tax related effects attributable to Memorial Resource restructuring and initial public offering                 (30,483)    
Other                 (227) 2,424 80
Net assets retained by previous owners                   (20,782)  
Balance 1,296,314       863,021       1,296,314 863,021 864,863
Tanos/Classic Properties [Member]                      
Equity Structure And Transactions [Line Items]                      
Balance                     50,853
Net income (loss)                     1,000
Net book value of net assets acquired by Partnership                     (50,639)
Distributions                     (1,214)
REO [Member]                      
Equity Structure And Transactions [Line Items]                      
Balance                     72,755
Net income (loss)                     28,691
Net book value of net assets acquired by Partnership                     (93,696)
Distributions                     (7,750)
WHT Properties [Member]                      
Equity Structure And Transactions [Line Items]                      
Balance               107,893   107,893 99,524
Net income (loss)                   (1,219) 8,369
Net book value of net assets acquired by Partnership                   (106,674)  
Balance                     107,893
Cinco Group [Member]                      
Equity Structure And Transactions [Line Items]                      
Balance               276,801   276,801 211,444
Net income (loss)                   12,494 8,233
Contributions                   7,233 64,597
Contribution of oil and gas properties                     6,893
Distribution attributable to net assets acquired                   55,281  
Net book value of net assets acquired by Partnership                   (297,627)  
Contribution related to sale of assets to NGP affiliate                     40,138
Net book value of net assets acquired by NGP affiliate                     (33,859)
Distributions                   (31,098) (20,553)
Other                   (2,302) (92)
Net assets retained by previous owners                   (20,782)  
Balance                     276,801
Property Swap [Member]                      
Equity Structure And Transactions [Line Items]                      
Balance       283,405       153,098 283,405 153,098 148,582
Net income (loss)                 (2,465) 40,737 (23,451)
Contributions                 5,990 89,570  
Distribution attributable to net assets acquired                     27,000
Distributions                 (9,886)   1,079
Distribution of net asset to MRD Holdco                 (26,131)    
Tax related effects attributable to Memorial Resource restructuring and initial public offering                 (30,483)    
Other                 227   (112)
Balance 220,657       283,405       220,657 283,405 153,098
Previous Owners [Member]                      
Equity Structure And Transactions [Line Items]                      
Balance       283,405       537,792 283,405 537,792 583,158
Net income (loss)                 (2,465) 52,012 22,842
Contributions                 5,990 96,803 64,597
Contribution of oil and gas properties                     6,893
Distribution attributable to net assets acquired                   55,281 27,000
Net book value of net assets acquired by Partnership                   (404,301) (144,335)
Contribution related to sale of assets to NGP affiliate                     40,138
Net book value of net assets acquired by NGP affiliate                     (33,859)
Distributions                 (9,886) (31,098) (28,438)
Distribution of net asset to MRD Holdco                 (26,131)    
Tax related effects attributable to Memorial Resource restructuring and initial public offering                 (30,483)    
Other                 227 (2,302) (204)
Net assets retained by previous owners                   (20,782)  
Balance $ 220,657       $ 283,405       $ 220,657 $ 283,405 $ 537,792