Additional cash contributions to plan.

No definition available.

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- Definition

Defined benefit contribution paid.

+ References

No definition available.

+ Details

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

- Definition

Defined benefit plan target asset allocation percentage.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Defined benefit plan target liability allocation percentage.

+ References

No definition available.

+ Details

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- Definition

Defined benefit plans deficit

+ References

No definition available.

+ Details

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- Definition

Defined benefit unfunded plans.

+ References

No definition available.

+ Details

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

- Definition

Maximum annual benefit accrual .

+ References

No definition available.

+ Details

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Namespace Prefix:	aeg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of pension plans.

+ References

No definition available.

+ Details

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Namespace Prefix:	aeg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Remaining average duration of defined benefits obligation.

+ References

No definition available.

+ Details

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Namespace Prefix:	aeg_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Retirement age.

+ References

No definition available.

+ Details

Name:	aeg_RetirementAge
Namespace Prefix:	aeg_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- 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

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

- Definition

The amount of employer contributions to retirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 26
-IssueDate 2019-01-01
-Paragraph 35
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=26&code=ifrs-tx-2019-en-r&anchor=para_35_b_i&doctype=Standard
-URIDate 2019-03-27

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount investment funds contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]; Investment funds [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 19
-IssueDate 2019-01-01
-Paragraph 142
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_142_f&doctype=Standard
-URIDate 2019-03-27

+ Details

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

- 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 2019-01-01
-Paragraph 140
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_140_a&doctype=Standard
-URIDate 2019-03-27

+ Details

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

- Definition

The amount other types of assets not separately disclosed contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2019-01-01
-Paragraph 142
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_142&doctype=Standard
-URIDate 2019-03-27

+ Details

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

- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2019-01-01
-Paragraph 141
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_141_g&doctype=Standard
-URIDate 2019-03-27

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2019-01-01
-Paragraph 57
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_57_a&doctype=Standard
-URIDate 2019-03-27

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Defined Benefit Plans - Additional Information (Detail) € in Millions	1 Months Ended		12 Months Ended
	Sep. 30, 2019 EUR (€)	Sep. 30, 2018 EUR (€)	Dec. 31, 2019 EUR (€) yr Plans	Dec. 31, 2018 EUR (€) yr	Jan. 01, 2018 yr	Dec. 31, 2017 EUR (€)
Disclosure of defined benefit plans [Line Items]
Defined benefit plans deficit			€ 388.0	€ (450.0)
Plan benefit liability			4,359.0	3,989.0		€ 3,950.0
Unfunded amount of defined benefit plans			2,487.0	1,956.0
Unfunded amount of other post employment defined benefit plans			767.0	€ 484.0
Retirement age \| yr				67
Defined benefit plan deficit			(386.0)	€ (502.0)
Maximum annual benefit accrual					1.875%
Aegon United Kingdom [member]
Disclosure of defined benefit plans [Line Items]
Defined benefit plan deficit			1.5	51.0
Contributions were paid into scheme			83.0	55.0
Additional contribution			29.0
Defined Benefit Amendment Plan 2019 [Member]
Disclosure of defined benefit plans [Line Items]
Defined benefit pension plan amount realised			101.0
Plan Amendment Average Life Expectancy [member]
Disclosure of defined benefit plans [Line Items]
Retirement age \| yr					68
United States [member] \| Supplemental pension and retirement plan [member]
Disclosure of defined benefit plans [Line Items]
Defined benefit plans unfunded			272.0	241.0
United States [member] \| Post employment healthcare benefits [member]
Disclosure of defined benefit plans [Line Items]
Plan benefit liability			€ 217.0	€ 210.0
Aegon United Kingdom [member]
Disclosure of defined benefit plans [Line Items]
Remaining average duration of defined benefits obligation \| yr			21.6	21.6
Percentage of investment assets allocation in primary equities			30.00%
Percentage of investment liability allocation in fixed interest and inflation-linked bonds and related derivatives			70.00%
Transamerica Corporation [member]
Disclosure of defined benefit plans [Line Items]
Employer contribution to pension plan	€ 223.0	€ 190.0
Aegon United States of America [member]
Disclosure of defined benefit plans [Line Items]
Number of benefit plans \| Plans			2
Remaining average duration of defined benefits obligation \| yr			12.6	12.2
Aegon Nederland N.V. [member]
Disclosure of defined benefit plans [Line Items]
Remaining average duration of defined benefits obligation \| yr			12.4	11.7
Unfunded amount of other post employment defined benefit plans			€ 65.0	€ 65.0
Aegon Nederland N.V. [member] \| Unfunded [member] \| Life insurance general account [member]
Disclosure of defined benefit plans [Line Items]
Remaining average duration of defined benefits obligation \| yr			21.9	20.9
Unfunded amount of defined benefit plans			€ 3,413.0	€ 2,967.0