Defined Benefit Plans - Summary of Amounts Recognized in Statement of Financial Positions (Detail) - EUR (€) € in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of net defined benefit liability (asset) [Line Items]
Present value of wholly or partly funded obligations	€ 4,604	€ 4,858
Fair value of plan assets	(4,717)	(4,466)
Surplus Deficit In Plan	(112)	392
Present value of wholly unfunded obligations	3,937	4,201
Ending Balance	3,824	4,593	€ 4,359
Retirement Benefit Plans [member]
Disclosure of net defined benefit liability (asset) [Line Items]
Present value of wholly or partly funded obligations	4,604	4,858
Fair value of plan assets	(4,717)	(4,466)
Surplus Deficit In Plan	(112)	392
Present value of wholly unfunded obligations	3,660	3,926
Ending Balance	3,547	4,318	4,076
Other Post Employment Benefit Plans [member]
Disclosure of net defined benefit liability (asset) [Line Items]
Present value of wholly or partly funded obligations
Fair value of plan assets
Surplus Deficit In Plan
Present value of wholly unfunded obligations	277	275
Ending Balance	€ 277	€ 275	€ 283

Unfunded defined benefit obligation present value.

No definition available.

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Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 57
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_57_a&doctype=Standard
-URIDate 2021-03-24

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 140
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_140_a&doctype=Standard
-URIDate 2021-03-24

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The fair value of any plan assets, less the present value of the defined benefit obligation. [Refer: Plan assets [member]]

+ References

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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