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Supplemental Balance Sheet Information - Asset Retirement Obligations (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Balance as of beginning of period $ 113 $ 119
Accretion expense 7 7
Liabilities incurred 3 2
Changes in estimated cash flows (4) (12)
Liabilities settled (3) (4)
Foreign currency translation 2 1
Balance as of end of period $ 118 113
Changes in estimated cash flows related to quarries   $ 8