Post-employee benefit plans (Tables)

6 Months Ended

Jun. 30, 2018

Employee Benefits [Abstract]

Components of post-employment benefit plans service cost

COMPONENTS OF POST-EMPLOYMENT BENEFIT PLANS SERVICE COST

		THREE MONTHS				SIX MONTHS
FOR THE PERIOD ENDED JUNE 30		2018		2017		2018		2017
DB pension		(53	)	(53	)	(106	)	(101	)
DC pension		(24	)	(24	)	(57	)	(55	)
OPEBs		(1	)	(1	)	(2	)	(3	)
Plan amendment gain on OPEBs		—		—		—		16
Less:
	Capitalized benefit plans cost	15		14		29		29
Total post-employment benefit plans service cost included in operating costs		(63	)	(64	)	(136	)	(114	)
Other costs recognized in severance, acquisition and other costs		—		(4	)	(4	)	(4	)
Total post-employment benefit plans service cost		(63	)	(68	)	(140	)	(118	)

Components of post-employment benefit plans financing cost

COMPONENTS OF POST-EMPLOYMENT BENEFIT PLANS FINANCING COST

	THREE MONTHS				SIX MONTHS
FOR THE PERIOD ENDED JUNE 30	2018		2017		2018		2017
DB pension	(5	)	(5	)	(11	)	(9	)
OPEBs	(12	)	(13	)	(23	)	(27	)
Total interest on post-employment benefit obligations	(17	)	(18	)	(34	)	(36	)