v3.25.4

Contract Liabilities - Additional Information (Detail) - EUR (€) € in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Contract Liabilities [Line Items] |  |  |
Revenue recognized from contract liabilities | € 5.9 | € 1.4 | € 13.3
Bottom of range [member] |  |  |
Contract Liabilities [Line Items] |  |  |
Expected revenue recognition period from non-current contract liabilities . | 1 year |  |
Top of range [member] |  |  |
Contract Liabilities [Line Items] |  |  |
Expected revenue recognition period from non-current contract liabilities . | 2 years |  |

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- Definition Contract liabilities [Line Items]. + References No definition available. + Details
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Namespace Prefix: | asnd_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Expected revenue recognition period from non-current contract liabilities . + References No definition available. + Details
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Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Revenue recognized from contract liabilities. + References No definition available. + Details
Name: | asnd_Revenuerecognizedfromcontractliabilities
Namespace Prefix: | asnd_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |