Leases - Right-of-use Assets (Details) $ in Thousands	12 Months Ended
Mar. 31, 2020 CAD ($)
Leases [Abstract]
Additions	$ 7,262
Terminations	(381)
Depreciation	(2,090)
Lease inducement allowance	3
Exchange rate effect	189
Ending balance	$ 11,492

Foreign Exchange Impact, Right-of-Use Assets

No definition available.

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- Definition

Lease Inducement Allowance, Right-of-use Assets

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Leases

+ References

No definition available.

+ Details

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- Definition

Termination of Right-of-use Assets

+ References

No definition available.

+ Details

Name:	alya_TerminationOfRightOfUseAssets
Namespace Prefix:	alya_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of additions to right-of-use assets. [Refer: Right-of-use assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2019-01-01
-Paragraph 53
-Subparagraph h
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_h&doctype=Standard
-URIDate 2019-03-27

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of depreciation of right-of-use assets. [Refer: Depreciation and amortisation expense; Right-of-use assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2019-01-01
-Paragraph 53
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_a&doctype=Standard
-URIDate 2019-03-27

+ Details

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- Definition

The amount of assets that represent a lessee's right to use an underlying asset for the lease term. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2019-01-01
-Paragraph 53
-Subparagraph j
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_j&doctype=Standard
-URIDate 2019-03-27

+ Details

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Balance Type:	debit
Period Type:	instant