long-term debt - TELUS Communications Inc. debentures (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 CAD ($) $ / NotesSeries	Dec. 31, 2017 CAD ($)
TELUS Communications Inc. debentures
Long-term debt	$ 14,101	$ 13,660
10.65% Debentures, Series 3
TELUS Communications Inc. debentures
Borrowings, interest rate	10.65%
Issued	June 1991
Maturity	June 2021
Borrowings, issue price \| $ / NotesSeries	998.00
Principal face amount: Originally issued	$ 175
Long-term debt	$ 175
9.65% Debentures, Series 5
TELUS Communications Inc. debentures
Borrowings, interest rate	9.65%
Issued	April 1992
Maturity	April 2022
Borrowings, issue price \| $ / NotesSeries	972.00
Principal face amount: Originally issued	$ 150
Long-term debt	$ 249
Period for exchange of debentures	4 years
Exchange of debentures	$ 99
8.80% Debentures, Series B
TELUS Communications Inc. debentures
Borrowings, interest rate	8.80%
Issued	September 1995
Maturity	September 2025
Borrowings, issue price \| $ / NotesSeries	995.10
Principal face amount: Originally issued	$ 200
Long-term debt	$ 200
Redemption present value spread - Basis points	0.15%
Redemption price percentage	100.00%
8.80% Debentures, Series B \| Minimum
TELUS Communications Inc. debentures
Redemption of debentures, notice period	30 days

The interest rate on borrowings. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The issue price of the borrowings per $1000 increment of debt.

+ References

No definition available.

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- Definition

Percentage price of original principal amount of borrowings at which borrowings can be redeemed by the issuer.

+ References

No definition available.

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- Definition

The redemption spread basis points.

+ References

No definition available.

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- Definition

Value of exchange of debentures under borrowings.

+ References

No definition available.

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- Definition

The date the debt instrument was issued.

+ References

No definition available.

+ Details

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- Definition

The date when the debt instrument is scheduled to be fully repaid.

+ References

No definition available.

+ Details

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- Definition

Total long-term borrowings, including the current and non-current portion.

+ References

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- Definition

Period for exchange of debentures under borrowings.

+ References

No definition available.

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- Definition

The notice period for redemption of debentures.

+ References

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- Definition

Pertains to the TELUS Communications Inc. debentures.

+ References

No definition available.

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