employee future benefits - Fair value measurements (Details) - Pension plans - CAD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair value measurements
Asset-backed securities	$ 30	$ 30
Cash, cash equivalents and other	621	338
Real estate	1,007	1,316
Fair value	9,380	9,043
Effect of asset ceiling limit	(121)	(263)
Fair value after asset ceiling	9,259	8,780
Fair value of administered pension benefit trusts	2	2
Quoted prices in active markets for identical items
Fair value measurements
Cash, cash equivalents and other	21	8
Fair value	2,990	2,779
Other
Fair value measurements
Asset-backed securities	30	30
Cash, cash equivalents and other	600	330
Real estate	1,007	1,316
Fair value	6,390	6,264
Canadian
Fair value measurements
Equity securities	979	1,048
Canadian \| Quoted prices in active markets for identical items
Fair value measurements
Equity securities	787	821
Canadian \| Other
Fair value measurements
Equity securities	192	227
Foreign
Fair value measurements
Equity securities	2,405	1,943
Foreign \| Quoted prices in active markets for identical items
Fair value measurements
Equity securities	663	581
Foreign \| Other
Fair value measurements
Equity securities	1,742	1,362
Government securities
Fair value measurements
Debt securities	1,698	1,494
Government securities \| Quoted prices in active markets for identical items
Fair value measurements
Debt securities	1,519	1,369
Government securities \| Other
Fair value measurements
Debt securities	179	125
Corporate debt securities
Fair value measurements
Debt securities	1,628	1,243
Corporate debt securities \| Other
Fair value measurements
Debt securities	1,628	1,243
Commercial mortgages
Fair value measurements
Debt securities	1,012	1,631
Commercial mortgages \| Other
Fair value measurements
Debt securities	$ 1,012	$ 1,631

The amount securities that are backed by underlying assets contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

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The amount cash and cash equivalents contribute to the fair value of defined benefit plan assets. [Refer: Cash and cash equivalents; Plan assets, at fair value; Defined benefit plans [member]]

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The amount instruments representing debt (rather than equity) contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

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The amount instruments representing equity (rather than debt) contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

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The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

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The amount real estate contributes to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

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The fair value of defined benefit plan assets, adjusted for any effect of limiting it to the asset ceiling. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. The asset ceiling is the present value of any economic benefits available in the form of refunds from the defined benefit plan or reductions in future contributions to the defined benefit plan.

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The fair value of assets of administered pension benefit trusts related to a legacy plan that was grandfathered prior to the merger between BC Telecom and TELUS Corporation. This plan holds no TELUS Common Shares, but holds debt of TELUS Corporation.

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Amount of reduction in fair value of plan assets due to limitation of plan surplus under asset ceiling provision.

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