Provisions (Tables)

12 Months Ended

Dec. 31, 2017

Other Provisions, Contingent Liabilities And Contingent Assets [Abstract]

Disclosure of other provisions

FOR THE YEAR ENDED DECEMBER 31	NOTE	Asset retirement obligations (AROs)		Other (1)		Total
January 1, 2017		175		137		312
Additions		14		46		60
Usage		(2	)	(30	)	(32	)
Reversals		(18	)	(12	)	(30	)
Acquired through business combinations		1		17		18
December 31, 2017		170		158		328
Current	18	11		44		55
Non-current	23	159		114		273
December 31, 2017		170		158		328

(1)Other includes environmental, legal, regulatory and vacant space provisions.