XML 126 R103.htm IDEA: XBRL DOCUMENT v3.3.1.900
Share-Based Compensation Plans - EQM Awards (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 12 Months Ended
Feb. 28, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Jan. 01, 2015
Jul. 31, 2012
Phantom units            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares outstanding   14,433        
Weighted average fair value, granted (in dollars per share)   $ 88.00 $ 58.79 $ 37.92    
Number of shares granted   2,220 2,580 3,790    
EQM Total Return Programs | Performance awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares outstanding         139,980 146,490
Weighted average fair value, granted (in dollars per share)   $ 20.02        
Volatility factor   38.00%        
Partnership distribution growth rate   10.00%        
Non-vested shares, forfeited   2,350        
Number of shares granted   137,630        
EQM Total Return Programs | Performance awards | Minimum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Percentage of unitholder return realized on common units from the date of grant   10.00%        
Volatility factor   27.00%        
EQM Total Return Programs | Performance awards | Maximum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Volatility factor   72.00%        
2014 EQM Value Driver Award Program            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares outstanding   28,696     62,845  
Weighted average fair value, granted (in dollars per share)   $ 58.79        
Award vested at end of year one (as a percent)     50.00%      
Award vested at end of year two (as a percent)     50.00%      
Shares of common stock 31,629          
Capitalized compensation cost   $ 0.1 $ 0.3