Reinsurance Assets - Summary of Reinsurance Assets Relating to Non-life Insurance (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disclosure of types of insurance contracts [Line Items]
Beginning balance	€ 18,910	€ 20,253
Ending balance	20,992	18,910
Non-Life insurance [member]
Disclosure of types of insurance contracts [Line Items]
Beginning balance	1,144	1,376
Gross premium and deposits – existing and new business	129	97
Unwind of discount / interest credited	83	87
Insurance liabilities released	(113)	(191)
Changes in unearned premiums	(75)	(38)
Incurred related to current year	91	20
Incurred related to prior years	49	32
Release for claims settled current year	(29)	(24)
Release for claims settled prior years	(108)	(130)
Change in IBNR	1	4
Net exchange differences	84	(103)
Other movements	(11)	13
Ending balance	€ 1,245	€ 1,144

Increase decrease through change in IBNR reinsurance assets.

No definition available.

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- Definition

Increase decrease through changes in unearned premiums reinsurance assets.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Increase decrease through incurred related to current year reinsurance assets.

+ References

No definition available.

+ Details

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- Definition

Increase decrease through incurred related to prior years reinsurance assets.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Increase decrease through insurance liabilities released reinsurance assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	aeg_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Increase decrease through other movements reinsurance assets.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Increase decrease through unwind of discount interest credited reinsurance assets.

+ References

No definition available.

+ Details

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- 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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- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 4
-IssueDate 2021-01-01
-Paragraph 37
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=4&code=ifrs-tx-2021-en-b&anchor=para_37_e&doctype=Standard&book=b
-URIDate 2021-03-24

+ Details

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- 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 2023-01-01
-Name IFRS
-Number 4
-IssueDate 2021-01-01
-Paragraph 37
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=4&code=ifrs-tx-2021-en-b&anchor=para_37_e&doctype=Standard&book=b
-URIDate 2021-03-24

+ Details

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- Details

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