employee future benefits - Fair value measurements (Details) - CAD ($) shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Fair value measurements
Fair value of administered pension benefit trusts	$ 2	$ 2
Pension plans
Fair value measurements
Asset-backed securities	6	32
Cash, cash equivalents and other	820	528
Real estate	1,025	1,085
Fair value	10,222	9,731
Beginning of year	(123)	(121)
Interest effect on asset ceiling limit	(3)	(4)
Changes in the effect of limiting net defined benefit assets to the asset ceilings	(53)	2
End of year	(179)	(123)
Fair value after asset ceiling	$ 10,043	9,608
Pension plans \| TELUS Corporation shares
Fair value measurements
Common Shares Issued	0
Pension plans \| TELUS International (Cda) Inc. share options
Fair value measurements
Common Shares Issued	0
Pension plans \| Quoted prices in active markets for identical items
Fair value measurements
Cash, cash equivalents and other	$ 37	20
Fair value	2,928	2,779
Pension plans \| Other
Fair value measurements
Asset-backed securities	6	32
Cash, cash equivalents and other	783	508
Real estate	1,025	1,085
Fair value	7,294	6,952
Pension plans \| Canadian
Fair value measurements
Equity securities	1,104	1,044
Pension plans \| Canadian \| Quoted prices in active markets for identical items
Fair value measurements
Equity securities	945	849
Pension plans \| Canadian \| Other
Fair value measurements
Equity securities	159	195
Pension plans \| Foreign
Fair value measurements
Equity securities	2,861	2,699
Pension plans \| Foreign \| Quoted prices in active markets for identical items
Fair value measurements
Equity securities	826	685
Pension plans \| Foreign \| Other
Fair value measurements
Equity securities	2,035	2,014
Pension plans \| Government securities
Fair value measurements
Debt securities	1,290	1,453
Pension plans \| Government securities \| Quoted prices in active markets for identical items
Fair value measurements
Debt securities	1,120	1,225
Pension plans \| Government securities \| Other
Fair value measurements
Debt securities	170	228
Pension plans \| Corporate debt securities
Fair value measurements
Debt securities	2,436	2,087
Pension plans \| Corporate debt securities \| Other
Fair value measurements
Debt securities	2,436	2,087
Pension plans \| Commercial mortgages
Fair value measurements
Debt securities	680	803
Pension plans \| Commercial mortgages \| Other
Fair value measurements
Debt securities	$ 680	$ 803

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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- Definition

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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- Definition

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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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from the gain (loss) on changes in the effect of limiting a net defined benefit asset to the asset ceiling, excluding amounts included in interest income or expense. [Refer: Interest income (expense); Net defined benefit liability (asset); Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)]

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- Definition

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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- Definition

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- Definition

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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- Definition

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.

+ References

No definition available.

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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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- Definition

The amount of interest effect on interest ceiling limit on plan asset in defined benefit pension plans.

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