Employee benefits, Sensitivity Analysis (Details)	Dec. 31, 2020
Changes in Principal Assumptions [Abstract]
Change in assumption by discount rate	0.50%
Change in assumption by annual salary increase	0.50%
Increase in assumption, discount rate	(9.00%)
Increase in assumption, annual salary increase	6.00%
Decrease in assumption, discount rate	10.00%
Decrease in assumption, annual salary increase	(7.00%)

The rate for present value of future retirement benefits cash flows, used to changes in principal assumptions on annual salary increase.

No definition available.

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The rate for present value of future retirement benefits cash flows, used to changes in principal assumptions on discount rate.

No definition available.

Name:	adn_DefinedBenefitObligationChangesInPrincipalAssumptionsOnDiscountRate
Namespace Prefix:	adn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

The rate for present value of future retirement benefits cash flows, used to decrease in principal assumptions on Annual salary increase.

No definition available.

Name:	adn_DefinedBenefitObligationDecreaseInPrincipalAssumptionsOnAnnualSalaryIncrease
Namespace Prefix:	adn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

The rate for present value of future retirement benefits cash flows, used to decrease in principal assumptions on discount rate.

No definition available.

Name:	adn_DefinedBenefitObligationDecreaseInPrincipalAssumptionsOnDiscountRate
Namespace Prefix:	adn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

The rate for present value of future retirement benefits cash flows, used to increase in principal assumptions on annual salary increase.

No definition available.

Name:	adn_DefinedBenefitObligationIncreaseInPrincipalAssumptionsOnAnnualSalaryIncrease
Namespace Prefix:	adn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

The rate for present value of future retirement benefits cash flows, used to increase in principal assumptions on discount rate.

No definition available.

Name:	adn_DefinedBenefitObligationIncreaseInPrincipalAssumptionsOnDiscountRate
Namespace Prefix:	adn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

No definition available.

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