PENSIONS AND OTHER POST RETIREMENT BENEFITS (Tables)

12 Months Ended

Dec. 31, 2019

PENSIONS AND OTHER POST RETIREMENT BENEFITS

Schedule of defined benefit obligations and funded status

			Pension Benefits				Other                   Post-Retirement                   Benefits
($ millions)			2019		2018		2019		2018
Change in benefit obligation
	Benefit obligation at beginning of year		6 730		6 717		557		597
	Obligations acquired through acquisition (note 32)		—		185		—		8
	Current service costs		220		235		13		13
	Plan participants' contributions		16		15		—		—
	Benefits paid		(293	)	(296	)	(24	)	(23	)
	Interest costs		255		236		22		21
	Foreign exchange		(13	)	14		(1	)	1
	Settlements		5		5		—		—
	Actuarial remeasurement:
		Experience gain arising on plan liabilities	(11	)	(26	)	(2	)	(18	)
		Actuarial gain arising from changes in demographic assumptions	—		(1	)	—		—
		Actuarial loss (gain) arising from changes in financial assumptions	799		(354	)	66		(42	)
Benefit obligation at end of year			7 708		6 730		631		557
Change in plan assets
	Fair value of plan assets at beginning of year		5 795		5 799		—		—
	Assets acquired through acquisition (note 32)		—		153		—		—
	Employer contributions		157		182		—		—
	Plan participants' contributions		16		15		—		—
	Benefits paid		(269	)	(273	)	—		—
	Foreign exchange		(8	)	14		—		—
	Settlements		5		5		—		—
	Administrative costs		(2	)	(2	)	—		—
	Income on plan assets		218		201		—		—
	Actuarial remeasurement:
		Return on plan assets greater than (less than) discount rate	781		(299	)	—		—
Fair value of plan assets at end of year			6 693		5 795		—		—
Net unfunded obligation			1 015		935		631		557

Schedule of defined benefit plan expenses

		Pension Benefits		Other                   Post-Retirement                   Benefits
($ millions)		2019	2018	2019	2018
Analysis of amount charged to earnings:
	Current service costs	220	235	13	13
	Interest costs	37	35	22	21
Defined benefit plans expense		257	270	35	34
Defined contribution plans expense		82	77	—	—
Total benefit plans expense charged to earnings		339	347	35	34

Components of defined benefit costs recognized in Other Comprehensive Income:

	Pension Benefits				Other                   Post-Retirement                   Benefits
($ millions)	2019		2018		2019		2018
Return on plan assets (excluding amounts included in net interest expense)	(781	)	299		—		—
Experience gain arising on plan liabilities	(11	)	(26	)	(2	)	(18	)
Actuarial loss (gain) arising from changes in financial assumptions	799		(354	)	66		(42	)
Actuarial gain arising from changes in demographic assumptions	—		(1	)	—		—
Actuarial loss (gain) recognized in other comprehensive income	7		(82	)	64		(60	)

Schedule of weighted average actuarial assumptions

	Pension Benefits		Other                   Post-Retirement                   Benefits
(%)	December 31 2019	December 31 2018	December 31 2019	December 31 2018
Discount rate	3.10	3.80	3.10	3.90
Rate of compensation increase	3.00	3.00	3.00	3.00

Schedule of changes in assumed assumptions

		Pension Benefits
($ millions)		Increase		Decrease
1% change in discount rate
	Effect on the aggregate service and interest costs	(25	)	31
	Effect on the benefit obligations	(988	)	1 271

		Other                   Post-Retirement                   Benefits
($ millions)		Increase		Decrease
1% change in discount rate
	Effect on the benefit obligations	(74	)	91
1% change in health care cost
	Effect on the aggregate service and interest costs	1		(1	)
	Effect on the benefit obligations	30		(26	)

Schedule of weighted average pension plan asset allocations based on market value

(%)		2019	2018
Equities, comprised of:
	– Canada	12	13
	– United States	19	17
	– Foreign	19	18
		50	48
Fixed income, comprised of:
	– Canada	41	43
Real estate, comprised of:
	– Canada	9	9
Total		100	100