Reinsurance Assets - Summary of Reinsurance Assets Relating to Non-life Insurance (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Disclosure of types of insurance contracts [Line Items]
Beginning balance	€ 19,202
Ending balance	20,507	€ 19,202
Non-life insurance [member]
Disclosure of types of insurance contracts [Line Items]
Beginning balance	1,327	1,481
Gross premium and deposits - existing and new business	84	99
Unwind of discount / interest credited	84	89
Insurance liabilities released	(123)	(129)
Changes to valuation of expected future benefits		28
Changes in unearned premiums	(28)	(42)
Incurred related to current year	77	85
Incurred related to prior years	36	37
Release for claims settled current year	(18)	(19)
Release for claims settled prior years	(130)	(119)
Change in IBNR	12	(8)
Shadow accounting adjustment	(24)	6
Net exchange differences	65	(180)
Portfolio transfers and acquisitions		2
Other movements	(8)	(4)
Ending balance	€ 1,356	€ 1,327

Increase decrease through change in IBNR reinsurance assets.

No definition available.

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

- Definition

Increase decrease through changes in unearned premiums reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through gross premium and deposits existing and new business reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through incurred related to current year reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through incurred related to prior years reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through insurance liabilities released reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through other movements reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through release for claims settled current year reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through release for claims settled prior years reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through shadow accounting adjustment reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

Increase decrease through unwind of discount interest credited reinsurance assets.

+ References

No definition available.

+ Details

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

- Definition

The amount of additions to reinsurance assets, other than those acquired through business combinations. [Refer: Business combinations [member]; Reinsurance assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 4
-IssueDate 2018-01-01
-Paragraph 37
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=4&date=2018-03-02&anchor=para_37_e&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

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

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfTypesOfInsuranceContractsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The increase (decrease) in reinsurance assets resulting from adjustments arising from the passage of time. [Refer: Reinsurance assets]

+ References

+ Details

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

- Definition

The increase (decrease) in reinsurance assets resulting from the net exchange differences arising when the financial statements are translated from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Reinsurance assets]

+ References

+ Details

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

- Definition

The amount of a cedant’s net contractual rights under a reinsurance contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 4
-IssueDate 2018-01-01
-Paragraph 37
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=4&date=2018-03-02&anchor=para_37_e&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_ReinsuranceAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	ifrs-full_TypesOfInsuranceContractsAxis=ifrs-full_NonlifeInsuranceContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: