Investments for Account of Policyholders - Summary of Investments in Real Estate for Account of Policyholders (Detail) - Investments in real estate [member] - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disclosure of investments for account of policyholders [Line Items]
Beginning balance	€ 467	€ 586
Additions	54
Subsequent expenditure capitalized	6	4
Disposals	(43)	(56)
Fair value gains / (losses)	46	(36)
Net exchange differences	32	(31)
Ending balance	€ 563	€ 467

Additions from investments for account of policyholders at fair value financial assets

No definition available.

Name:	aeg_AdditionsFromInvestmentsForAccountOfPolicyholdersAtFairValueFinancialAssets
Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Disclosure of investments for account of policyholders.

+ References

No definition available.

+ Details

Name:	aeg_DisclosureOfInvestmentsForAccountOfPolicyholdersLineItems
Namespace Prefix:	aeg_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Disposals of investments for account of policyholders at fair value financial assets.

+ References

No definition available.

+ Details

Name:	aeg_DisposalsOfInvestmentsForAccountOfPolicyholdersAtFairValueFinancialAssets
Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Fair value gains losses of investments for account of policyholders at fair value financial assets.

+ References

No definition available.

+ Details

Name:	aeg_FairValueGainsLossesOfInvestmentsForAccountOfPolicyholdersAtFairValueFinancialAssets
Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Investments for account of policyholders financial assets at fair value through profit or loss, excluding derivatives and including investments in real estate

+ References

No definition available.

+ Details

Name:	aeg_InvestmentsForAccountOfPolicyholdersFinancialAssetsAtFairValueThroughProfitOrLossExcludingDerivativesAndIncludingInvestmentsInRealEstate
Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Net exchange differences of investments for account of policyholders at fair value financial assets.

+ References

No definition available.

+ Details

Name:	aeg_NetExchangeDifferencesOfInvestmentsForAccountOfPolicyholdersAtFairValueFinancialAssets
Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Subsequent expenditure capitalized investments for account of policyholders at fair value financial assets.

+ References

No definition available.

+ Details

Name:	aeg_SubsequentExpenditureCapitalizedInvestmentsForAccountOfPolicyholdersAtFairValueFinancialAssets
Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	aeg_InvestmentsAxis=aeg_InvestmentsInRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: