CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	Dec. 31, 2019	Dec. 31, 2018
Limited partners' capital account, units outstanding (in units)	233,289,537
Shell Pipeline Company L P
General partners' capital account, units issued (in units)	4,761,012	4,567,588
General partners' capital account, units outstanding (in units)	4,761,012	4,567,588
Common unitholders | General Public
Limited partners' capital account, units issued (in units)	123,832,233	12,383,233
Limited partners' capital account, units outstanding (in units)	123,832,233	123,832,233
Common unitholders | Shell Pipeline Company L P
Limited partners' capital account, units issued (in units)	109,457,304	99,979,548
Limited partners' capital account, units outstanding (in units)	109,457,304	99,979,548