v3.7.0.1
Related-Party Transactions, Summary of Affiliate Transactions (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Feb. 14, 2017
Feb. 03, 2017
Jan. 18, 2017
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Subsequent Event            
Revenues       $ 715 $ 615 $ 497
Operating and maintenance expenses       166 135 111
Imbalance settlement gains and reimbursements from Tesoro [1]       (24) (42) (43)
General and administrative expenses       69 72 39
Imbalance settlement gains       (7) (8) (17)
Reimbursements from Tesoro       17 34 26
Quarterly cash distributions, including IDRs       $ (245) $ (148) $ (87)
Subsequent Event            
Subsequent Event            
Cash distributions paid per unit     $ 0.91      
Cash distribution to Tesoro $ 140   $ 77      
Date of distribution Feb. 14, 2017          
Distribution Made to Limited Partner, Declaration Date   Feb. 03, 2017 Jan. 18, 2017      
[1] Includes net imbalance settlement gains of $7 million, $8 million and $17 million in the years ended December 31, 2016, 2015 and 2014, respectively. Also includes reimbursements primarily related to pressure testing and repairs and maintenance costs pursuant to the Amended Omnibus Agreement and the Carson Assets Indemnity Agreement of $17 million, $34 million and $26 million in the years ended December 31, 2016, 2015 and 2014, respectively.